SOLUTION: Please help me solve this cross multiplying proportion problem; 5/8 over 5/4 = y over 3/2

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Question 689233: Please help me solve this cross multiplying proportion problem;
5/8 over 5/4 = y over 3/2
Found 2 solutions by gatorEngineer, MathTherapy:
Answer by gatorEngineer(3) About Me  (Show Source):
You can put this solution on YOUR website!
You have %285%2F8%29%2F%285%2F4%29= y%2F%283%2F2%29
To cross multiply we multiply the denominators (5/4) and (3/2) to the opposite sides (creating a cross) like so:
---------
step 1: take (5/4) to the right by multiplying (5/4) on both sides
%285%2F4%29%2A%285%2F8%29%2F%285%2F4%29= %285%2F4%29%2Ay%2F%283%2F2%29
(5/4)/(5/4) on the left cancel each other out because it equals 1
%285%2F8%29=%285%2F4%29%2Ay%2F%283%2F2%29
---------
step 2: take (3/2) to the left by multiplying (3/2) on both sides
%283%2F2%29%2A%285%2F8%29=%283%2F2%29%2A%285%2F4%29%2Ay%2F%283%2F2%29
(3/2)/(3/2) on the right cancel each other out because it equals 1
%283%2F2%29%2A%285%2F8%29=%285%2F4%29%2Ay
---------
step 3: simplify the left by multiplying numerators and denominators (top and bottom)
%283%2A5%29%2F%282%2A8%29=%285%2F4%29%2Ay
15%2F16=%285%2F4%29%2Ay
---------
step 4: solve for y by multiplying by 4 and dividing by 5 on both sides(also known as multiplying by the reciprocal fraction (4/5))
%2815%2F16%29%2A%284%2F5%29=y%2A%285%2F4%29%2A%284%2F5%29
%28%2815%2A4%29%2F%2816%2A5%29%29=%28%285%2A4%29%2F%284%2A5%29%29%2Ay
%28%2815%2A4%29%2F%285%2A16%29%29=%28%285%2A4%29%2F%285%2A4%29%29%2Ay
%2815%2F5%29%2A%284%2F16%29=+%285%2F5%29%2A%284%2F4%29%2Ay
%283%2F1%29%2A%281%2F4%29=+%281%29%2A%281%29%2Ay
%283%2F4%29=+y
y=.75

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!
Please help me solve this cross multiplying proportion problem;
5/8 over 5/4 = y over 3/2

%285%2F8%29%2F%285%2F4%29+=+y%2F%283%2F2%29

%285%2F8%29%284%2F5%29+=+y%282%2F3%29 ------ Separating each side to make it less confusing, changing division to multiplication, and inverting divisors in the process

%28cross%285%29%2F2cross%288%29%29%28cross%284%29%2Fcross%285%29%29+=+y%282%2F3%29

1%2F2+=+2y%2F3

4y = 3 ------ Cross-multiplying

y+=+3%2F4, or highlight_green%28.75%29

You can do the check!!

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