First son: 7x
Second son: 3x
Third son: 5x
Sum of the inheritance: Php 14,250,000
Equation:
7x + 3x + 5x = 14 250 000
15x = 14 250 000
15x/15 = 14 250 000
x = 950 000
Amount of inheritance each will receive:
First son: 7 (950 000) = Php 6 650 000
Second son: 3 (950 000) = Php 2,850 000
Third son: 5 (950 000) = Php 4 750 000
Check:
Php 6 650 000 + Php 2 850 000 + Php 4 750 000 = Php 14 250 000