Tank C contained 3 times as many guppies as Tank D. When 20% of the guppies in Tank C and 10% of the guppies in Tank D were transferred to Tank E, Tank E had 42 guppies, which was 20% more guppies than before. How many less guppies were there in Tank D than Tank C in the end?
|
Tank C |
Tank D |
Tank E |
Before |
3 u |
1 u |
5x0.7 = 3.5 u |
Change |
- 0.6 u |
- 0.1 u |
+ 1x0.7 = + 0.7 u |
After |
2.4 u |
0.9 u |
6x0.7 = 4.2 u |
Number of guppies that were transferred from Tank C to Tank E
= 20% x 3 u
=
20100 x 3 u
= 0.6 u
Number of guppies that were transferred from Tank D to Tank E
= 10% x 1 u
=
10100 x 1 u
= 0.1 u
20% =
20100 =
15Some guppies from Tank C and Tank D were transferred to Tank E. The total number of guppies transferred from Tank C and Tank D into Tank E is the same.
Total number of guppies transferred from Tank C and Tank D into Tank E
= 0.6 u + 0.1 u
= 0.7 u
4.2 u = 42
1 u = 42 ÷ 4.2 = 10
Number of less guppies in Tank D than Tank C
= 2.4 u - 0.9 u
= 1.5 u
= 1.5 x 10
= 15
Answer(s): 15