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HbgBill

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It's been WAY too many years. I know it's simple.. but, I can't pull it up in my memory.

If something costs $1.19/Lb How much does 1 kg cost?

I know 1 lb is 0.45 kg so 1 kg is a bit less than half the cost of a pound

Is it something like 1.19/16 = x/1000?

My recipe calls for 11.3 lbs of a material at 1.19 lb. This equates to 5.1 kg.

Thanks, Bill
 
HbgBill said:
It's been WAY too many years. I know it's simple.. but, I can't pull it up in my memory.

If something costs $1.19/Lb How much does 1 kg cost?

I know 1 lb is 0.45 kg so 1 kg is a bit less than half the cost of a pound

Is it something like 1.19/16 = x/1000?

My recipe calls for 11.3 lbs of a material at 1.19 lb. This equates to 5.1 kg.

Thanks, Bill
Click to expand...

Basically to start with, you just want to convert from dollars per pound to dollars per kilogram. So you know two things: you are starting with $1.19/lb, and you know that 1 lb is about .45 kg.

Just take your starting value and multiply by "1" (Since something divided by "something it is equal to" equals "1"). When we multiply by 1, we are not changing the value, just the units in which we are expressing something:

($1.19/lb)(1 lb/.45 kg) = ?

Notice that in the first expression, "lb" is on the bottom (denominator), and in the second expression, "lb" is on the top (numerator). Therefore, the "lbs" cancel each other out, and the units left are $/kg.

($1.19/lb)(1 lb/.45 kg) = $2.64/kg (approx.)

You can now apply this to whatever amount of kg you have. So in this case, if you have 5.1 kg, you have

(5.1 kg)($2.64/kg) = ?

Notice the "kg" top and bottom cancel out, and your are left with units in $.

Hope that helps.
 
HbgBill said:
It's been WAY too many years. I know it's simple.. but, I can't pull it up in my memory.

If something costs $1.19/Lb How much does 1 kg cost?

I know 1 lb is 0.45 kg so 1 kg is a bit less than half the cost of a pound

Is it something like 1.19/16 = x/1000?

My recipe calls for 11.3 lbs of a material at 1.19 lb. This equates to 5.1 kg.

Thanks, Bill
Click to expand...
Well 5.1 kg cost the same as 11.3 lbs which is 11.3lbs*$1.19/lb=$13.45. Now divide $13.45 by 5.1kg to find the cost of 1 kg
 
Denis said:
Wonder why 11.3 pounds is so popular
Click to expand...

Because that's the value you entered. :roll:

If you had entered 311, instead (for example), then you'd get a pageful of hits from conversion sites referencing 311.
 
Thanks for the clear write-up.. but I'm having trouble with it.. I'm sure it's that I'm brain dead..

If something costs $1.19/lb.. and 1 kg is less than 1/2 lb.. shouldn't the price of a kg be less than half that of a pound? In the example.. it the price is more than double the pound price.

What my ORIGINAL thought was:

1.19 is to 1lb as X is to 0.45 which would make the price roughly half.. or $0.53/kg

I couldn't figure that equation until just now.
 
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Your reasoning is sound. If 1 kilogram were indeed about half a pound, then the price would be about half as much. However, think about that assumption for a moment - let's say a kilogram is ~0.45 pounds. That makes your original recipe call for \(\displaystyle \frac{11.3\:lb}{1}\cdot \frac{1\:lb}{0.45\:kg}=25.11\:kg\). And you know that's not the case, so the assumption must be faulty. In reality, the relationship is the other way around. 1 pound is ~0.45 kilograms.
 
HbgBill said:
Thanks for the clear write-up.. but I'm having trouble with it.. I'm sure it's that I'm brain dead..

If something costs $1.19/lb.. and 1 kg is less than 1/2 lb.. shouldn't the price of a kg be less than half that of a pound? In the example.. it the price is more than double the pound price.

What my ORIGINAL thought was:

1.19 is to 1lb as X is to 0.45 which would make the price roughly half.. or $0.53/kg

I couldn't figure that equation until just now.
Click to expand...
Let us assume that 1 lbs equals 1/2 kg. Then 2lbs= 1kg. Not the other way around.
 
Yah, thanks guys, I woke up in the middle of the night to take a pee.. got back in bed and that popped up in my old brain. I had it backwards.

Appreciate the clarification... presented in such a nice way. :)

Bill
 
Back with a similar question.......

If 1 oz of something costs $2.50.. how much is 1 hectogram? One hectogram is about 3.53 ounces..

Argghh.. this higher math is getting me.

I think this is the final question about recipe costs.

Thanks again for any help.
 
HbgBill said:
Back with a similar question.......

If 1 oz of something costs $2.50.. how much is 1 hectogram? One hectogram is about 3.53 ounces..

Argghh.. this higher math is getting me.

I think this is the final question about recipe costs.

Thanks again for any help.
Click to expand...
I will give you two ways of solving this.
1) if 1 oz cost $2.50 then how much is 2 oz? Answer, 2*$2.50. How much is 7 ozs? Answer is 7*$2.50. So much is 3.53 oz? Answer, just compute 3.53*$2.50
2) Never be afraid to multiply by 1. Just realize that things like 1 week/7days=1, 1foot/12 inches = 1, 36 inches/1 yd=1...
Now in your case 1 oz= $2.50 so 1 oz/$2.50=1 and $2.50/1 oz =1
You want to change 3.53 oz into $ so you multiply by 1
3.53 oz = 3.53 oz * 1 = 3.53 oz * $2.50/oz = 3.53*$2.50 (note that the ozs cancelled out). Whenever you want to change the way something looks all you have to do is multiply by 1!!!!
 
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HbgBill said:
You make it sound so simple.. Thank you for being patient with me..

Bill
Click to expand...
Whenever you do a problem it should be so simple. If it is not then you are thinking about it wrong.
I actually had 2 students in one of my classes who went to the chairperson to complain that I make things insultingly easy. My chairperson through the students out of her office. I guess the students wanted me to make things harder. Amazing!
 
I would love to have had you for a teacher.. I always struggled with math. Thanks again.
 
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