Adding Whole numbers

[manchester78]

Can anyone show me how to solve this problem?
3-1/2+4-3/4

 

[Deleted member 4993]

Can anyone show me how to solve this problem?
3-1/2+4-3/4

Is your problem:

\(\displaystyle 3 - \frac{1}{2} + 4 - \frac{3}{4}\) ...............(1).................This is what you posted................. OR

\(\displaystyle \frac{3-1}{2} + \frac{4-3}{4}\) ...............(2)...This should be written as (3-1)/2 + (4-3)/4.... those parentheses are super-important ...OR

something else....

To evaluate any of these start with PEMDAS (or BODMAS)

 

[Dr.Peterson]

Can anyone show me how to solve this problem?
3-1/2+4-3/4

It's also possible that you mean (3 1/2) + (4 3/4), that is, [MATH]3\frac{1}{2}+4\frac{3}{4}[/MATH], a sum of mixed numbers, as some people (but never within mathematics) use a hyphen to tie together the whole and fractional parts.

In any case, we need to see not only what your problem is, but how you are confused by it. And the best way to show that is to make an attempt at solving it, so we can see what is going wrong.

If by chance you meant my version, then you solve it by adding the two whole numbers, then adding the two fractions, and then combining those. Your difficulty is likely in the last step, so I'll particularly want to see your work there. That's true of the other interpretations, too.

 

[manchester78]

Thank you for both your responses. I was taking practice aptitude test for a job and that’s how it was written. 3-1/2+4-3/4
The answers that were given were:
7-1/4
7-5/8
8-1/2
8-1/4
The answer was 8-1/4. This makes no sense to me

Is your problem:

\(\displaystyle 3 - \frac{1}{2} + 4 - \frac{3}{4}\) ...............(1).................This is what you posted................. OR

\(\displaystyle \frac{3-1}{2} + \frac{4-3}{4}\) ...............(2)...This should be written as (3-1)/2 + (4-3)/4.... those parentheses are super-important ...OR

something else....

To evaluate any of these start with PEMDAS (or BODMAS)

 

[Deleted member 4993]

Thank you for both your responses. I was taking practice aptitude test for a job and that’s how it was written. 3-1/2+4-3/4
The answers that were given were:
7-1/4
7-5/8
8-1/2
8-1/4
The answer was 8-1/4. This makes no sense to me

So those are mixed numbers - as suggested in response #3. So add those up

by first converting those to "improper" fractions or​

​

as suggested in response #3

you solve it by adding the two whole numbers, then adding the two fractions, and then combining those.​

​

 

[Steven G]

If you have 3 quarters (as in the coin) and you add a half (a dollar) then you will have 5 quarters which is 1 1/4. Now add on the 7 (3+4) to get 8 1/4

 

[pka]

Thank you for both your responses. I was taking practice aptitude test for a job and that’s how it was written. 3-1/2+4-3/4
The answers that were given were:
7-1/4
7-5/8
8-1/2
8-1/4
The answer was 8-1/4. This makes no sense to me

\(\left. \begin{gathered}
3\frac{1}{2} = \frac{7}{2} = \frac{{14}}{4} \hfill \\
4\frac{3}{4} = \frac{{19}}{4} = \frac{{19}}{4} \hfill \\
\end{gathered} \right\rangle = \dfrac{{33}}{4} = 8\dfrac{1}{4}\)

 

[Dr.Peterson]

Thank you for both your responses. I was taking practice aptitude test for a job and that’s how it was written. 3-1/2+4-3/4
The answers that were given were:
7-1/4
7-5/8
8-1/2
8-1/4
The answer was 8-1/4. This makes no sense to me

As I've said, no mathematician would write "3-1/2+4-3/4"; I'd think it would be confusing even to mere mortals. But I suspect this aptitude test was for some field (carpentry?) where such notation may be common; and very likely it used words, like "add 3-1/2 and 4-3/4", in which case it makes more sense (as this is a common recommendation of style guides for writing).

Others have demonstrated two ways to do this addition. It ends up being 3+4, plus 1/2+3/4, and the latter is the same as 2/4+3/4 = 5/4 = 1 1/4. If you need more help with this, search for "adding mixed numbers". Here is one page you'll find: https://www.mathsisfun.com/numbers/fractions-mixed-addition.html