Gabriel, Wesley and Calvin collected erasers in the ratio of 10 : 10 : 9. After Calvin gave ¹₅ to Gabriel and Wesley, Calvin had 31 less erasers than Gabriel. The number of erasers that Wesley had increased by 15%. How many erasers did Gabriel and Calvin have in the end?

	Gabriel	Wesley	Calvin
Before	10 u	10 u	9 u
Change	+ 0.3 u	+ 1.5 u	- 1.8 u
After	10.3 u	11.5 u	7.2 u

Number of erasers that Calvin gave to Gabriel and Wesley
= ¹₅ x 9 u
= 1.8 u

Number of erasers that Wesley received from Calvin
= ¹⁵₁₀₀ x 10 u
= 1.5 u

Number of erasers that Gabriel received from Calvin
= 1.8 u - 1.5 u
= 0.3 u

Number of less erasers that Calvin had less than Gabriel
= 10.3 u - 7.2 u 
= 3.1 u

3.1 u = 31

1 u = 31 ÷ 3.1 = 10

Number of erasers that Gabriel and Calvin had
= 10.3 u + 7.2 u
= 17.5 u
= 17.5 x 10
= 175

Answer(s): 175