At first, there were 405 more men than women at the zoo. By 3 p.m., a total of 264 men and women left the zoo. There were as many men as women who left the zoo. In the end, there were 4 times as many men as women who remained behind. How many men were at the zoo at first?
|
Men |
Women |
Difference |
Before |
4 u + 132 |
1 u + 132 |
405 |
Change |
- 132 |
- 132 |
|
After |
4 u |
1 u |
3 u |
Since there was the same number of women and men that left, the difference between the number of women and men remains unchanged.
3 u = 405
1 u = 405 ÷ 3 = 135
Number of men in the end
= 4 u
= 4 x 135
= 540
Number of men that left
= 264 ÷ 2
= 132
Number of men at first
= 540 + 132
= 672
Answer(s): 672