SOLUTION: Patty is 12 years old, she is 4 years more than twice as old as John. How old is John ?

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Question 1190674: Patty is 12 years old, she is 4 years more than twice as old as John. How old is John ?
Answer by greenestamps(13200) About Me  (Show Source):
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Using formal algebra....

x = John's age (what we are looking for)
2x = twice John's age
2x+4 = 4 more the twice John's age (Patty's age)

Patty's age is 12:

2x+4=12
2x=8
x=4

ANSWER: John is 4 years old

Informally -- to get some good exercise in logical reasoning....

Subtract 4 from Patty's age to get 8 -- to account for the "4 years older"; then
Divide the 8 by 2 to get 4 -- to account for the "twice as old as"

Again of course the answer is 4.