John Mortal
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Please, check my calculations
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John Mortal
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It's not modern values of inch and foot. Those values from a RPG, but it doesn't mutter in this case. I just need a bit of a help with checking. ?
Dr.Peterson
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Please show the exact wording of the exercise you are doing. It is unclear what is given and what you are asked to do, including how much you are told to round. If it is not something you were assigned to do, tell us what your goal is.
John Mortal
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It's not an exercise. My goal is just check those calculations, please. Did I work out for it correctly? I just tried to find how many feet into 71 inches. Also, how many feet into 71 inches by a fraction form. So, I calculated it and now I just need a bit of help with checking those results that I found. Yes, a modern inch is not 2.46 cm, but ignore it. In this case one inch is 2.46.
Dr.Peterson
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I see that there are some historical "feet" that were about 29.6 cm, so I'll take that as what you were given.
Starting with that (and a foot containing 12 inches), and supposing that your goal is to convert 71 such inches to centimeters, I would do this:
[math]71\text{ in}\times\frac{1\text{ ft}}{12\text{ in}}\times\frac{29.6\text{ cm}}{1\text{ ft}}=175.13\text{ cm}[/math]
So your calculations are a little off, in large part due to inappropriate rounding.
Doing equivalent calculations step by step, I find that
[math]1\text{ in}=29.6\text{ cm}\div 12=2.467\text{ cm}[/math][math]71\text{ in}=71\times2.467\text{ cm}=175.13\text{ cm}[/math]
You incorrectly rounded 2.467 down to 2.46 (but then never used that).
Then, although you correctly converted 71 inches to [imath]5\frac{11}{12}[/imath] feet, you never used that, but reverted to dividing 71 by 12 as a decimal.
Then you rounded that to 6 feet, losing all the precision you had gained by using the fraction, in effect adding a full inch to the answer. So, not surprisingly, your answer is 2 to 3 centimeters too high (that is, about an inch).
John Mortal
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Why is it 12? 12 in * 2.46 cm = 29.52 cm, but if we calculate 12.02 in * 2.46 cm = 29.5692 or 29.6 сm.
Also, do you mean that I don't need to convert that fraction (71/12) into a decimal, right? If I convert it hence I make a mistake. Do I understand you correctly?
John Mortal
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And...you have broken my mind with these calculations though. May I ask you to give me step-by-step calculation for this formula, please? ?
Dr.Peterson
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Why did you use 12? Because there are 12 inches in a foot, right? I don't know why you would ask that.
Where did you get 12.02 inches? This makes no sense.
As I pointed out, the correct length of an inch is 2.467, not 2.46; the latter comes from your inappropriate rounding. Multiplying the former by 12, you get 29.604. Both your calculations and mine differ from exactly 29.6 because of rounding (which can't be avoided).
As I said, you first converted 71/12 to a fraction, but never used that result, because it was not helpful. Then you converted it to a decimal (that is, you divided 71 by 12), which was appropriate. That's the part you got right!
What you did wrong was to round as much as you did.
In the first line you cite, I did more or less what you presumably did at the start:
[math]1\text{ in}=29.6\text{ cm}\div 12=2.467\text{ cm}[/math]
Since a foot is 29.6 cm, and an inch is 1/12 of a foot, an inch is 1/12 of 29.6 cm. I divided 29.6 by 12 and got 2.467. That's what you did here:
In the second line,
[math]71\text{ in}=71\times2.467\text{ cm}=175.13\text{ cm}[/math]
I multiplied the length of an inch, 2.467 cm, by 71 to find the length of 71 inches in centimeters. This is exactly what you did here, except that I used the better value:
So I have no idea why you are confused.
John Mortal
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Okay, I see 71 inches 175.13 см. After it I need to work out for how many feet within 175.13 cm.
I know that 1 foot is 29.6 cm and I have 175.13 cm.
I need to divide 175.13 by 29.6 to find how many feet it is, right? ?
And I do it 175.13 / 29.6 = 5.916554054054054 (I just check it out with a calculator)
So, 5.916554054054054 is a too long number. I should round it up.
5.916554054054054 ≈ 6 feet and it means 6 feet ≈ 71 inches
Okay, maybe is it likely as my next example?
5.916554054054054 = 5.92 feet and it means 5.92 feet = 71 inches = 175.13 cm
Is it correct? I'm sorry...?
Dr.Peterson
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In my first response, I asked what your goal is. You said,
If I'm right now, then you got the answer, 5 11/12 feet. which can also be stated as 5 feet, 11 inches.
But why did you do all these calculations that ended up with centimeters? That's irrelevant to your stated goal.
But, again, there is no need to bring in centimeters, which only add potential errors. All you had to do is to divide 71 by 12 and get 5.9166..., and round that to 5.92 feet.
What would be even more helpful would be to tell us your ultimate goal: What do you want to do with the answer when you get it? You say it's for an RPG, but that doesn't tell us much. Knowing more details would help us decide what form of answer will be most useful, including how much accuracy you need.
I missed this because it was delayed for moderation, I think; it appears that the answer to my question is that your goal is to convert 71 inches to feet. If so, then centimeters have nothing to do with it, and my subsequent work was aiming at the wrong goal, which appeared to be the number of centimeters, since that's where your work ended up. (This is why I asked for your goal, which is to do the calculations to find a number of feet. Your goal for us was "to check the calculations", but that's not what I asked for.)
If I'm right now, then you got the answer, 5 11/12 feet. which can also be stated as 5 feet, 11 inches.
But why did you do all these calculations that ended up with centimeters? That's irrelevant to your stated goal.
Trying to read into this what your real goal is, you seem to be going in circles using centimeters. You say again that you want to find a number of feet, and you end up with the (reasonably rounded) value of 5.92 feet. (Rounding to a whole number of feet is not very accurate; rounding to two decimal places as you did at the end is reasonable.) But then, again you end with a number of centimeters instead.
But, again, there is no need to bring in centimeters, which only add potential errors. All you had to do is to divide 71 by 12 and get 5.9166..., and round that to 5.92 feet.
What would be even more helpful would be to tell us your ultimate goal: What do you want to do with the answer when you get it? You say it's for an RPG, but that doesn't tell us much. Knowing more details would help us decide what form of answer will be most useful, including how much accuracy you need.
John Mortal
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There is two formulas how to find a height and weight of character.
1. 58 + 4D6''' (4D6 is four 6 sided dice)
2. 4D6 * 30 + (Str * 10) + 40
First formula for a height
Second formula for a weight
71 - 58 = 13, so I have rolled 13 on 4D6.
It means 58 + 13 = 71'' is a height of character
Str is a Strength mod. and Str equals to -1 in that case.
Next, I need to roll 4D6 for the second formula. It was 14 on 4D6.
14 * 30 + (-1 * 10) + 40 = 72 lbs is a weight of character.
Within that game there is two determiners for pounds.
1. Weight-pound (wlb) = 6 kg
2. Bowl-pound (lb) = 0.5 kg
I need to multiply 72 lbs by 0.5 kg to know how many kilograms 72 Bowl-pounds are.
72 * 0.5 = 36 kg
So, I have tried to find how many centimeters in 71 inches to see final results within cm and kg of a character.
And, yes, I try to find how many it is in kg and cm, also how many it is in feet, inches and lbs.
Dr.Peterson
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What are the units here? Apparently the height is in inches; is the weight in pounds? If you want to clearly state the problem, you need to say things like that.
How do you get 72? I get 450. But at least now I know it's pounds.
I wonder if the 30 is supposed to be 3 (or you used 3 instead of 30).
I have no idea what any of this means. What is a "determiner"? Are you saying that "pound" means different things at different times?
This doesn't answer my question at all. You've added in the issue of pounds, but haven't shown any reason you want to convert anything to centimeters.
But if you just want to know out of curiosity, then do whatever you want.
John Mortal
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Yes, a weight in lbs (pounds) and height in inches, but also, I need to know how many feet and centimeters in 71" and how many kilograms in 72 pounds (lbs).
Yes, you're right. I have made a mistake. It's not 30, but it is 3. 14 * 3 + (-1 * 10) + 40 = 72
So...I just show you that list with measurements and an explanation from a text where from those different sorts of pounds are.
My reason is I need to convert those inches, pounds into centimeters and kilograms. That is
That is very confusing.
To the best of my knowledge, the terms “weight-pound” and “bowl-pound” are not historically meaningful unlike “cloth yard.” The mark was a term meaning half a pound.
If you are doing historical work, weights and measures were standardized primarily on a local basis; international and national standardization was a development of the late eighteenth and early nineteenth cebtury. The modern term “Troy ounces” is derived from the measures used during the late Middle Ages in the town of Troyes, one of the locations of the Fairs of Chanpagne. So, if you are trying to do serious historical research, these tables are worthless unless limited to some specific locality, Bruges for example.
As for the math, it is straight forward, they are telling you to use the approximation 12 pounds = 6 kilograms, which equates to 1 pound is approximately 1 pound = 500 grams.
To the best of my knowledge, the terms “weight-pound” and “bowl-pound” are not historically meaningful unlike “cloth yard.” The mark was a term meaning half a pound.
If you are doing historical work, weights and measures were standardized primarily on a local basis; international and national standardization was a development of the late eighteenth and early nineteenth cebtury. The modern term “Troy ounces” is derived from the measures used during the late Middle Ages in the town of Troyes, one of the locations of the Fairs of Chanpagne. So, if you are trying to do serious historical research, these tables are worthless unless limited to some specific locality, Bruges for example.
As for the math, it is straight forward, they are telling you to use the approximation 12 pounds = 6 kilograms, which equates to 1 pound is approximately 1 pound = 500 grams.
Dr.Peterson
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Interesting. If that's the world you're in, I suppose you accept it.
What I see here is that you have all the conversion factors you need, and you've shown that you can use them.
The one remaining issue is that that incorrect factor of 2.46 cm is not your own work, but was given to you. If you divide 29.6 cm by 12, you get 2.46666..., which rounds to 2.47, not 2.46, as I've said before; so if you use that, you'll have a bit of an error in your results.
But since you haven't said why you need these conversions, I'll just assume that this amount of error is acceptable in your context, and there's nothing more to be said.
What I see here is that you have all the conversion factors you need, and you've shown that you can use them.
The one remaining issue is that that incorrect factor of 2.46 cm is not your own work, but was given to you. If you divide 29.6 cm by 12, you get 2.46666..., which rounds to 2.47, not 2.46, as I've said before; so if you use that, you'll have a bit of an error in your results.
But since you haven't said why you need these conversions, I'll just assume that this amount of error is acceptable in your context, and there's nothing more to be said.
John Mortal
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I don't say I do some historical work. This is tables from a RPG game. That RPG game about the ancient world, yes. And it doesn't matter, actually. I mean that numbers are numbers everywhere.
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John Mortal
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Well, I have those tables and numbers only. This is rules of that game. ?
Actually, that game about the ancient world as I have wrote about it above. It seems to me that all calculations are so-so there. It's for the sake of atmosphere of the ancient world, vibes of it (a description of that rule book gives me to know it). Anyway, I need to calculate it, because I understand something in that game by calculations. A height, weight, amount of XP, how large your land is (your property), etc. All of it I find with formulas that game gives me with its rules.
You mean that 1 foot = 12 inches (in the context of that game). It means that 12 inches = 12 * 2.46 cm = 29.52 cm, but 1 foot is 1 = 29.6 cm.
I have wrote you I need to convert it
. 'I need' is my reason . Well, it doesn't matter why I need it, I think. This is a forum about maths. Maths = numbers, numbers to you calculate these numbers. You see numbers in that game, I see numbers in that game hence calculate it. Another something, if you don't have a wish to calculate it, so it's no problem. Just don't do it. You have helped me a lot already. Thank you!John Mortal
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It seems to me I found correct answers.
1 inch = 2.46 cm
1 foot = 29.6 cm
12.02 inches * 2.46 cm = 29.5692 = 29.6 cm
1 foot = 12.02 inches
12.02 inches = 29.5692 cm or 29.6 cm
71 inches * 2.46 cm = 174.66 cm
71 inches = 174.66 cm
174.66 cm / 29.6 cm = 5.900675675675676 = 5.9 feet
5.9 feet * 12.02 inches = 70.918 = 71 inches
Dr.Peterson
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Not knowing details about how such games work, I would expect that you would do everything within that world and its units, and wouldn't need to convert to metric. Any calculations you really need to do for the game, I'd think would be within their historical or imaginary system of units. And if you want to convert to familiar units, just in order to understand how big things are, that's fine; precision is not important.Well, I have those tables and numbers only. This is rules of that game. ?
Actually, that game about the ancient world as I have wrote about it above. It seems to me that all calculations are so-so there. It's for the sake of atmosphere of the ancient world, vibes of it (a description of that rule book gives me to know it). Anyway, I need to calculate it, because I understand something in that game by calculations. A height, weight, amount of XP, how large your land is (your property), etc. All of it I find with formulas that game gives me with its rules.
But again, I don't know how these things work, and this doesn't really matter.
What I've tried to explain about this is that the numbers you're given are inconsistent. I'm supposing that the length of a foot is primary, and I showed that the inch would be 2.47 cm, not 2.46. You're apparently supposing that the inch is primary, and showing that the length of a foot would be 29.52 cm, not 29.6. We're both saying the same thing: that their numbers don't quite fit together. So if you want to convert accurately and not get confused, you need to pick one as the "real" conversion, and ignore the other. (Whichever unit you start with, they have erred in their rounding.)
This is not your fault, but theirs, since you didn't work out one number from the other as I initially assumed. Just don't expect exactly consistent results, and you should be able to get by.
I think we've done all the calculations you've asked about. If there's something you think is missing, please once again show your attempt, and we'll probably tell you you're right, since you've done correct calculations so far.
One more time: Your calculations have been correct, apart from the fact that the numbers you are given are not quite accurate. I think the latter is probably what is troubling you, and I want you to know that any errors you run across are (probably) their fault, and not yours.
(I was locked out of the site for an hour, as sometimes happens; and it happened again while I was adding this postscript. I wrote the above before your last message. It looks like we agree, except that 12.02 is irrelevant; 12 is the one exact number you were given. None of the "errors" are big enough to worry about, and your methods are correct. It's just the rounding that is off.)