Question 1059955: Sally is 8 years older than john. John is 14 years older than Karen. If the sum of their ages is 90, how old are they?
Found 2 solutions by ikleyn, josmiceli:
Answer by ikleyn(52787)   (Show Source):
You can put this solution on YOUR website! .
Sally is 8 years older than john. John is 14 years older than Karen. If the sum of their ages is 90, how old are they?
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Let K be the Karen's age.
Then the John's age is (K+14) years, and Sally's age is (K+14)+8 = K + 22 years.
As the condition says, the sum of ages is 90, which gives you an equation
K + (K+14) + (K+22) = 90.
Simplify and solve for K:
3K + 36 = 90,
3K = 90 - 36,
3K = 54,
K =  = 18.
Answer. Karen is 18 years old. John is 18+14 = 32 years old. Sally is 32+8 = 40 years old.
The lesson to learn from this solution:
1. First choose the major unknown reasonably.
2. Second, express other unknowns via the major unknown.
3. Then make an equation.
4. Then solve the equation.
It is the algorithm.
Answer by josmiceli(19441)  (Show Source):
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