1 - 4/7 = 3/7
1 - 3/4 = 1/4
Since they had an equal amount of money left, 1/4 of Xavier's money is equal to 3/7 of Reina's money
Concept here is : Equal fractions
Make the numerator the same.
1/4 = 3/12
So we can say :
Xavier had 12 units of money at first.
Reina had 7 units of money at first.
Difference = 12 units - 7 units = 5 units
5 units = $105
1 unit = $105 ÷ 5 = $21
They each had 3 units left in the end.
Total they had in the end = 3 units + 3 units = 6 units
= 6 × $21 = $126