SOLUTION: mary is 2x as old as her sister jessie. if the sum of their ages is 18 how old are both sisters

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Question 929086: mary is 2x as old as her sister jessie. if the sum of their ages is 18 how old are both sisters
Answer by ewatrrr(24785)   (Show Source): You can put this solution on YOUR website!
x the sister's age
Mary + sister = 18
.........
2x + x = 18
3x = 18
x = 6, the sister's age. Mary is 12
And...checking
sum = 18

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