Tank U contained 2 times as many guppies as Tank V. When 10% of the guppies in Tank U and 40% of the guppies in Tank V were transferred to Tank W, Tank W had 120 guppies, which was 25% more guppies than before. How many more guppies were there in Tank W than Tank V in the end?

	Tank U	Tank V	Tank W
Before	2 u	1 u	4x0.6 = 2.4 u
Change	- 0.2 u	- 0.4 u	+ 1x0.6 = + 0.6 u
After	1.8 u	0.6 u	5x0.6 = 3 u

Number of guppies that were transferred from Tank U to Tank W
= 10% x 2 u
= ¹⁰₁₀₀ x 2 u
= 0.2 u

Number of guppies that were transferred from Tank V to Tank W
= 40% x 1 u
= ⁴⁰₁₀₀ x 1 u
= 0.4 u

25% = ²⁵₁₀₀ = ¹₄

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

Total number of guppies transferred from Tank U and Tank V into Tank W
= 0.2 u + 0.4 u
= 0.6 u

3 u = 120

1 u = 120 ÷ 3 = 40

Number of more guppies in Tank W than Tank V
= 3 u - 0.6 u
= 2.4 u
= 2.4 x 40
= 96

Answer(s): 96