Answer:
Andy = 84 and Bart = 105
Step-by-step explanation:
Given that the ratio is 4 : 5 = 4x : 5x
Andy loses 9 thus 4x - 9
ratio 4x - 9 : 5x = 5 : 7, that is
[tex]\frac{4x-9}{5x}[/tex] = [tex]\frac{5}{7}[/tex] ( cross- multiply )
25x = 7(4x - 9) ← distribute
25x = 28x - 63 ( subtract 28x from both sides )
- 3x = - 63 ( divide both sides by 3 )
x = 21
Hence
Andy = 4x = 4 × 21 = 84 marbles
Bart = 5x = 5 × 21 = 105 marbles
