SOLUTION: John's mother is 23 years older than John. The product of their ages is 518. How old are John and his mother ?
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-> SOLUTION: John's mother is 23 years older than John. The product of their ages is 518. How old are John and his mother ?
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Question 499692: John's mother is 23 years older than John. The product of their ages is 518. How old are John and his mother ? Answer by Maths68(1474) (Show Source):
You can put this solution on YOUR website! Let
Present age of John = j
Present age of mother = m
John's mother is 23 years older than John
if we subtract 23 years from mother's age John and mother will of same age
j=m-23 .......(1)
Product of their ages = 518
j*m=518 .......(2)
Put the value of j from (1) to (2)
j*m=518
(m-23)m=518
m^2-23m-518=0
Now solve for m
m^2+14m-37m-518=0
m(m+14)-37(m+14)=0
(m+14)(m-37)=0
m+14=0 or m-37=0
m=-14 or m=37
m=-14 is impossible so mothers is 37 years old
Put the value of m in equation (1)
j=m-23
j=37-23
j=14
John is 14 years old
