SOLUTION: Rover was 5 years older than Yolanda. In 10 years he found that 4 times his age exceede twice Yolanda's age by only 50. How old were Rover and Yolanda in the beginning? I tried to
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-> SOLUTION: Rover was 5 years older than Yolanda. In 10 years he found that 4 times his age exceede twice Yolanda's age by only 50. How old were Rover and Yolanda in the beginning? I tried to
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Question 1103354: Rover was 5 years older than Yolanda. In 10 years he found that 4 times his age exceede twice Yolanda's age by only 50. How old were Rover and Yolanda in the beginning? I tried to solve this, but my answers wouldn't solve. Could you help me learn how? Thank you! Found 2 solutions by ikleyn, greenestamps:Answer by ikleyn(52858) (Show Source):
In Math terms, the condition says THIS:
R = Y + 5 (1) ("Rover was 5 years older than Yolanda.")
4*(R + 10) = 2*(Y+10) + 50. (2) ("In 10 years . . . 4 times his age exceeds twice Yolanda's age by only 50.")
Simplify (2):
4R + 40 = 2Y + 20 + 50,
4R = 2Y + 70 - 40
4R = 2Y + 30. (3)
Next, substitute (1) into eq(3). You will get
4*(Y+5) = 2Y + 30, or
4Y + 20 = 2Y + 30,
2Y = 30 - 20 = 10 ====> Y = = 5.
Then from (1) R = Y + 5 = 5+5 = 10.
Answer. At the beginning, R was 10 years old; Y was 5 years old.
My thought for setting up this problem was to use the ages after the 10 years to set up the problem. Rover will always be 5 years older the Yolanda, so
let x = Yolanda's age after the 10 years
then x+5 is Rover's age then
The problem says 4 times Rover's age at this time is 50 more than twice Yolanda's age:
Yolanda's age after the 10 years is 15, so her age at the beginning was 5; that means Rover's age at the beginning was 10.
