At the farm, the cow population increased by 25% in the second month and then by a further 20% in the next 3 months. If there were 900 cows in the end, how many cows were there at the farm at first?
|
Cows |
Before |
100% |
Change 1 |
+ 25% |
After 1 |
125% |
Change 2 |
+ 25% |
After 2 |
150% |
Population of cows at first = 100%
New population of cows after first increase
= 100% + 25%
= 125%
Percentage of second increase
= 20% x 125%
=
20100 x 125%
= 25%
New population of cows after second increase
= 125% + 25%
= 150%
150% of cow population = 900
1% of the cow population
= 900 ÷ 150
= 6
100% of cow population
= 100 x 6
= 600
Number of cows at first = 600
Answer(s): 600