Question 1095287: The sum of age of matt and Sam is 29,sam and Ben 26,ben and Matt 31,how old is the youngest?
Found 3 solutions by KMST, ikleyn, MathTherapy:
Answer by KMST(5328)   (Show Source):
Answer by ikleyn(52926)  (Show Source):
You can put this solution on YOUR website! .
We are given
M + S = 29, (1)
S + B = 26, (2)
B + M = 31. (3)
Add all three equations (1), (2) and (3). You will get
2M + 2S + 2B = 29 + 26 + 31 = 86.
Divide by 2 both sides of the last equation. You will get
M + S + B = 43. (4)
Now, subtract eq(1) from eq(4). You will get
B = 43 - 29 = 14. ====> Ben is 14 years old.
Next, subtract eq(2) from eq(4). You will get
M = 43 - 26 = 17. ====> Matt is 17 years old.
Finally, subtract eq(3) from eq(4). You will get
S = 43 - 31 = 12. ====> Sam is 12 years old.
Answer. Sam is the youngest, and he is 12 years old. Ben is 14 and Matt is 17 years old.
Check. M + S = 17 + 12 = 29;
S + B = 12 + 14 = 26;
B + M = 14 + 17 = 31.
Solved.
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To see many other problems, solved by the similar method, look into the lesson
- The tricks to solve some word problems with three and more unknowns using mental math
in this site.
Answer by MathTherapy(10558)  (Show Source):
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