Sarah and Shiyun collected beads. Sarah gave 30% of her beads to Shiyun and as a result, Shiyun's beads increased by 10%. If Sarah had 77 beads left, find the number of beads Shiyun should give to Sarah in the end so that both had an equal number of beads.

	Sarah	Shiyun	Comparing the change in Shiyun's beads
Before	10x1 = 10 u		10x3 = 30u
Change	- 3x1 = - 3 u	+ 3x1 = + 3 u	+ 1x3 = + 3 u
After	7x1 = 7 u		11x3 = 33 u

30% = ³⁰₁₀₀ = ³₁₀
10% = ¹⁰₁₀₀ = ¹₁₀

The increase in the number of beads that Shiyun had is repeated.  Make the increase in the number of beads that Shiyun had the same. LCM of 3 and 1 = 3

7 u = 77

1 u = 77 ÷ 7 = 11

Number of beads that Shiyun had more than Sarah in the end
= 33 u - 7 u
= 26 u

Number of beads that Shiyun should give to Sarah so that both had an equal number of beads in the end
= 26 u ÷ 2
= 13 u
= 13 x 11
= 143

Answer(s): 143