tolong yah pakai caranya..makasih..

4.
P : Q = 7 : 4
jumlah usia mereka = 33, maka..

P = 7/(7+4). 33
P = 7/11 .33
P = 7. 3
P = 21

Q = 4/(7+4).33
Q = 4/11.33
Q = 4.3
Q = 12

usia 2 thn lalu
P = 21-2 = 19
Q = 12-2 = 10

perbandingan usia 2 thn lalu
19 : 10