Tank B contained 4 times as many guppies as Tank C. When 30% of the guppies in Tank B and 30% of the guppies in Tank C were transferred to Tank D, Tank D had 90 guppies, which was 20% more guppies than before. How many more guppies were there in Tank D than Tank C in the end?
|
Tank B |
Tank C |
Tank D |
Before |
4 u |
1 u |
5x1.5 = 7.5 u |
Change |
- 1.2 u |
- 0.3 u |
+ 1x1.5 = + 1.5 u |
After |
2.8 u |
0.7 u |
6x1.5 = 9 u |
Number of guppies that were transferred from Tank B to Tank D
= 30% x 4 u
=
30100 x 4 u
= 1.2 u
Number of guppies that were transferred from Tank C to Tank D
= 30% x 1 u
=
30100 x 1 u
= 0.3 u
20% =
20100 =
15Some guppies from Tank B and Tank C were transferred to Tank D. The total number of guppies transferred from Tank B and Tank C into Tank D is the same.
Total number of guppies transferred from Tank B and Tank C into Tank D
= 1.2 u + 0.3 u
= 1.5 u
9 u = 90
1 u = 90 ÷ 9 = 10
Number of more guppies in Tank D than Tank C
= 9 u - 0.7 u
= 8.3 u
= 8.3 x 10
= 83
Answer(s): 83