SOLUTION: Can you please help me solve this problem: The sum of the ages of Mike and Dan is 20 years and four years dans age will be a 3/4 of mikes age how old is mike now?

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Question 1137922: Can you please help me solve this problem: The sum of the ages of Mike and Dan is 20 years and four years dans age will be a 3/4 of mikes age how old is mike now?
Found 3 solutions by josmiceli, josgarithmetic, math_helper:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Not clearly written. Must be able to understand
in order to solve

Answer by josgarithmetic(39616) About Me  (Show Source):
You can put this solution on YOUR website!
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The sum of the ages of Mike and Dan is 20 years. In four more years Dan's age will be a 3/4 of mikes age. How old is Mike now?
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system%28m%2Bd=20%2Cd%2B4=%283%2F4%29%28m%2B4%29%29

system%28d=20-m%2C4%28d%2B4%29=3%28m%2B4%29%29

4%2820-m%2B4%29=3m%2B12
80-4m%2B16=3m%2B12
80%2B16-12=3m%2B4m
84=7m
highlight%28m=12%29

Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!


M = Mike's age

D = Dan's age




M + D = 20               (eq 1)




In four years:

(D + 4) = (3/4)(M + 4)   (eq 2)






You now have two equations in two unknowns.  One way to solve this system

is to substitute for M (M = 20 - D) from (eq 1) into (eq 2) to get a form of (eq 2) that only has variable D.   Then solve for D.



Once you have D, plug that value into (eq 1) to get M.  Be sure to check that the answers for D & M work in (eq 2).