If a farmer has 90 animals in a field.4/9 are sheep,1/3 are cows,1/10 are horses and the rest are pigs.How many pigs are there?

3 answers

I don't know the answer
4/9*90 = 40 are sheep, 1/3* 90 =30 are cows, 1/10*90 = 9 are horses. What is left?
First you need to change these fractions to equivalent fractions with the same denominator. The smallest number divisible by 9, 3, and 10 is 90

4/9 = 40/90
1/3 = 30/90
1/10 = 9/90

Add them together and the sum is 79/90. 90/90 - 79/90 = 11/90

11 are pigs.