SOLUTION: Sally is 6 years more than twice as old as Sue. The difference between their ages is 48 years. How old is Sally?

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Question 1152053: Sally is 6 years more than twice as old as Sue. The difference between their ages is 48 years. How old is Sally?
Found 3 solutions by josgarithmetic, greenestamps, MathTherapy:
Answer by josgarithmetic(39613) About Me  (Show Source):
You can put this solution on YOUR website!
y, Sally
u, Sue

Literal description as a system of equations:
system%28y=6%2B2u%2Cabs%28y-u%29=48%29


Two possible choices from the absolute value; one of them should work and the other should not work.

That means, one of these will work and the other may not work:
system%28y=6%2B2u%2Cy-u=48%29
OR
system%28y=6%2B2u%2Cu-y=48%29

Answer by greenestamps(13195) About Me  (Show Source):
You can put this solution on YOUR website!


Using two variables to set up the problem makes for a lot of extra work....

The difference in their ages is 48 years; and Sally is older. So

x = Sue's age
x+48 = Sally's age

Then write and solve the equation that says Sally's age is 6 more than twice Sue's age:

x%2B48+=+2x%2B6
42+=+x

ANSWER: Sue is 42; Sally is 42+48 = 90.


Answer by MathTherapy(10549) About Me  (Show Source):
You can put this solution on YOUR website!

Sally is 6 years more than twice as old as Sue. The difference between their ages is 48 years. How old is Sally?
Let Sue's age be S
As it's crystal clear that Sally is older, we get: 2S + 6 - S = 48
S, or Sue = 48 - 6 = 42
Sally's age: highlight_green%28matrix%281%2C3%2C+42+%2B+48%2C+%22=%22%2C+90%29%29