The masses are M and (4 - M) using the equation for universal gravitation

F = GM(4 - M)/R²

FR²/G = M(4 - M)

(2.5*10 - 10)*(0.20)²/6.67*10-11 = M(4 - M)

0.1*10 - 10/6.67*10 - 11 = 4M - M2

0.15 = 4M - M2

M2 - 4M + 0.15 = 0

After solving the Quadratic equation

We get:-

M1 = 0.0378 kg

M2 = 3.962 kg.

m1+m2=4.5

6.67*10^-11*m1*m2 / .04 = 2.5*10^-10

solve 2 equations --->m1=0.034 kg , m2 = 4.466 kg