Question 1156608
When bob was 12 his grandmother was 5 times of his age and minus 1/2 of his sister’s age (which was half of bob’s age).
Now bob’s granny is 60. How old is bob now?
:
let y = no. of years ago that this was true.
Bob was 12, so sister was 6
5(12) - 6 = 60 - y
60 - 6 = 60 - y
y = 60 - 54
y = 6 years
:
12 + 6 = 18 yrs is Bob's present age