There are 9 more penguins than hippopotamuses in a zoo. If there is a total of 126 legs, how many penguins are there in the zoo?
| |
Hippopotamuses |
Penguins |
Total |
| Number |
1 u |
1 u + 9 |
|
| Value |
4 |
2 |
|
| Total value |
4 u |
2 u + 18 |
6 u + 18 |
Number of hippopotamuses = 1 u
Number of penguins = 1 u + 9
Number of hippopotamuses' legs
= 4 x 1 u
= 4 u
Number of penguins' legs
= 2(1 u + 9)
= 2 u + 18
Total number of legs
= 4 u + 2 u + 18
= 6 u + 18
6 u + 18 = 126
6 u = 126 - 18
6 u = 126 - 18
6 u = 108
1 u = 108 ÷ 6 = 18
Number of penguins
= 1 u + 9
= 18 + 9
= 27
Answer(s): 27
