SOLUTION: John is twice as old as Sally and Sally is three times as old as Mary. There total age is 100 years. How old is each person?

Question 925952: John is twice as old as Sally and Sally is three times as old as Mary. There total age is 100 years. How old is each person?
Answer by TimothyLamb(4379) (Show Source): You can put this solution on YOUR website!
x = john age
y = sally age
z = mary age
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x = 2y
y = 3z
x + y + z = 100
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put the system of linear equations into standard form
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x - 2y = 0
y - 3z = 0
x + y + z = 100
---
copy and paste the above standard form linear equations in to this solver:
https://sooeet.com/math/system-of-linear-equations-solver.php
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solution:
x = john age = 60
y = sally age = 30
z = mary age = 10
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Solve systems of linear equations up to 6-equations 6-variables:
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