Question 699133
The present age of A and his father is in the ratio of 2:5 respectively.
{{{a/f}}} = {{{2/5}}}
Cross multiply
5a = 2f
a = {{{2/5}}}f
a = .4f
:
4 years hence the ratio of their ages will become 5:11 respectively.
{{{((a+4))/((f+4))}}} = {{{5/11}}}
cross multiply
11(a+4) = 5(f+4)
11a + 44 = 5f + 20
11a = 5f + 20 - 44
11a = 5f - 24
replace a with .4f
11(.4f) = 5f - 24
4.4f = 5f - 24
24 = 5f - 4.4
24 = .6f
f = 24/.6
f = 40 yrs is Dad's present age
then
a = .4(40)
a = 16 is A's present age
:
what was father's age 5 years ago? You can figure that out, I know