Tank Q contained 3 times as many guppies as Tank R. When 20% of the guppies in Tank Q and 40% of the guppies in Tank R were transferred to Tank S, Tank S had 150 guppies, which was 25% more guppies than before. How many more guppies were there in Tank S than Tank R in the end?

	Tank Q	Tank R	Tank S
Before	3 u	1 u	4x1 = 4 u
Change	- 0.6 u	- 0.4 u	+ 1x1 = + 1 u
After	2.4 u	0.6 u	5x1 = 5 u

Number of guppies that were transferred from Tank Q to Tank S
= 20% x 3 u
= ²⁰₁₀₀ x 3 u
= 0.6 u

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

25% = ²⁵₁₀₀ = ¹₄

Some guppies from Tank Q and Tank R were transferred to Tank S.  The total number of guppies transferred from Tank Q and Tank R into Tank S is the same.

Total number of guppies transferred from Tank Q and Tank R into Tank S
= 0.6 u + 0.4 u
= 1 u

5 u = 150

1 u = 150 ÷ 5 = 30

Number of more guppies in Tank S than Tank R
= 5 u - 0.6 u
= 4.4 u
= 4.4 x 30
= 132

Answer(s): 132