Math 221
posted by Erica .
Math 221  Ms. Sue, Sunday, July 13, 2014 at 2:24pm
I've done several problems for you. Now it's your turn.
How do you think this problem should be solved?
Answer this Question I was thinking that I should multiply the numerators and denominators

as with most problems involving fractions, work first with the denominators. They cannot be added or subtracted unless they all have the same denominator.
5/12 + 7/9
The GCD(12,9) = 36. So, what you have is
15/36 + 28/36
Now all the "units" are the same. Just as you cannot add apples and oranges, you cannot add twelfths and ninths. But you can add a bunch of 36ths. Since 15+28=43, the final answer is just 43/36.
Or, if you must, 1 7/36
Respond to this Question
Similar Questions

Math
Do you know of a good website that can help me with word problems? 
4th grade math
I need help on how to write a mixed number as a fraction 4 9/17 77/17 multiply 17 times 4 + 9. then put the # u get on top and keep the bottom # Thanks Mike 4 9/17 is the same as (17*4 + 9 )/17 where * means times. thanks erny 11 9+4=13 … 
materials science engineering
Identify the [221] vector.(crystallographic directions qns) The answer given corresponds to 0.5 in x direction,0.5 in y and 1 in z. Why is it not [1 1 0.5], the simply reduced form. The ans is the reciprocal of [221], which puzzles … 
Math 221
Math 221  Ms. Sue, Sunday, July 13, 2014 at 1:22pm (13/15) / (7/10) (13/15) * (10/7) = Multiply the numerators together. Multiply the denominators together. What do you get? 
Math 221
what is the perimeter of a square using 13ft. Math 221  Ms. Sue, Sunday, July 13, 2014 at 1:56pm Is 13 ft the length of a side of the square? 
Math 221
Need help please explain how to get the answers for these two factoring problems and for the second problem with the "ac method". 2a^2+1+3a 15x^2+31x+2 
Math 221
Need help please explain how to get the answers for these two factoring problems and for the second problem with the "ac method". 2a^2+1+3a 15x^2+31x+2 
math fractions
•math  Ms. Sue, Sunday, November 16, 2014 at 12:39pm 12 •math  bob, Sunday, November 16, 2014 at 12:56pm Ms. Sue can you tell me how you got that answer please. •math  Ms. Sue, Sunday, November 16, 2014 at 1:09pm Multiples … 
6th Grade Math Inequalities
The maximum weight allowed on The Wildcat ride is 221 pounds. Your friend weighs 60 pounds. To be able to ride in a car together, how much can you weigh? 
English
1. What day is July 22?  It is Sunday. 2. What day is on July 22?