Tank W contained 4 times as many guppies as Tank X. When 30% of the guppies in Tank W and 30% of the guppies in Tank X were transferred to Tank Y, Tank Y had 225 guppies, which was 25% more guppies than before. How many more guppies were there in Tank Y than Tank X in the end?

	Tank W	Tank X	Tank Y
Before	4 u	1 u	4x1.5 = 6 u
Change	- 1.2 u	- 0.3 u	+ 1x1.5 = + 1.5 u
After	2.8 u	0.7 u	5x1.5 = 7.5 u

Number of guppies that were transferred from Tank W to Tank Y
= 30% x 4 u
= ³⁰₁₀₀ x 4 u
= 1.2 u

Number of guppies that were transferred from Tank X to Tank Y
= 30% x 1 u
= ³⁰₁₀₀ x 1 u
= 0.3 u

25% = ²⁵₁₀₀ = ¹₄

Some guppies from Tank W and Tank X were transferred to Tank Y.  The total number of guppies transferred from Tank W and Tank X into Tank Y is the same.

Total number of guppies transferred from Tank W and Tank X into Tank Y
= 1.2 u + 0.3 u
= 1.5 u

7.5 u = 225

1 u = 225 ÷ 7.5 = 30

Number of more guppies in Tank Y than Tank X
= 7.5 u - 0.7 u
= 6.8 u
= 6.8 x 30
= 204

Answer(s): 204