SOLUTION: Jack is now 7 times as old as Jill. If 10 years from now, he will 3 years as old as Jill, how old is Jack now?

Question 518295: Jack is now 7 times as old as Jill. If 10 years from now, he will 3 years as old as Jill, how old is Jack now?
Answer by Maths68(1474) (Show Source): You can put this solution on YOUR website!
Let
Present age of Jack = j
Present age of Jill = i

Jack is now 7 times as old as Jill.
j=7i.......(1)
If 10 years from now,
after 10 years Jack will be = j+10
after 10 years Jill will be = i+10
Then
he will 3 years as old as Jill, how old is Jack now?
j+10=(i+10)+3
j+10=i+10+3
j=i+10+3-10
j=i+3
Put the value of j from (1) to above equation
7i=i+3
7i-i=3
6i=3
6i/6=6/3
i=1/2
Put the value of i in (1)
j=7i
j=7 * 1/2
j=7/2
j=3.5

Present age of Jack = j = 3 and half years old
Present age of Jill = i = half year old.

RELATED QUESTIONS
Three years from now Jack will be three times as old as Jill Jack is ten years older than (answered by ewatrrr)

Jack is twice as old as Jill. In 2 years, Jack will be 4 times as old as Jill was 9 years (answered by TakeATuition.com)

Jack is twice as old as Jill. In 2 years, Jack will be 4 times as old as Jill was 9... (answered by ankor@dixie-net.com)

jack is twice as old as jill. in two years, jack will be 4 times as old as jill was 9... (answered by rwm)

Jack is twice as old as Jill. In 2 years, Jack will be 4 times as old as Jill was 9 years (answered by ramkikk66)

Jack is twice as old as Jill.In 2 years, Jack will be four times as old as Jill was 9... (answered by josgarithmetic,MathLover1)

Jack is twice as old as Jill was, when Jack was as old as Jill is now. Together Jack and... (answered by drj)

two years ago, Jill was 7 times as old as Jack. Three years from now, Jill will be 4... (answered by lwsshak3)

Jack is now 14 years older than Jill. If in 10 years Jack will be twice as old as Jill,... (answered by ptaylor)