SOLUTION: Mary's age and Bob's age are in the ration 3:2. Eight years later, the ratio of their ages will be 4:3. Find their present ages.

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Question 205841: Mary's age and Bob's age are in the ration 3:2. Eight years later, the ratio of their ages will be 4:3. Find their present ages.
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
m = Mary's age; b = Bob's age
:
Mary's age and Bob's age are in the ration 3:2.
m%2Fb = 3%2F2
cross multiply
2m = 3b
m = 3%2F2b
or
m = 1.5b
:
Eight years later, the ratio of their ages will be 4:3.
%28m%2B8%29%2F%28b%2B8%29 = 4%2F3
Cross multiply
3(m+8) = 4(b+8)
3m + 24 = 4b + 32
3m = 4b + 32 - 24
3m = 4b + 8
:
Find their present ages.
Replace m with 1.5b in the above equation
3(1.5b) = 4b + 8
4.5b = 4b + 8
4.5b - 4b = 8
.5b = 8
b = 8%2F.5
b = 16 yr is Bob's present age
then
m = 1.5(16)
m = 24 yrs is Mary's present age
;
:
Check solution in the 8 yr equation
32%2F24 = 4%2F3