Question

Of the 60 animals on a certain farm, 2/3 are either pigs or cows. How many of the animals are cows? (1) The farm has more than twice as many cows as pigs (2) The farm has more than 12 pigs.

Answer 1

Explanation:

`(2)/(3)of total=` either cow or pigs

`(2)/(3)of 60=`

`(2)/(3) X 60=40`

Either pigs or cow = 40

(1) Let number of pigs be x

then number of cows >twice of pigs = 2x

number of pigs + number of cows = 40

number of cows = 40 -x

40-x > 2x

40 > 3x

x <
`(40)/(3)`

x < 12.33

nearest integral number is 12

so its 12

so number of pigs will be 12 so that number of cows = 40 -12 = 28

which is more than twice of number of pigs

28 > 2( 12) = 24

(2) number of pigs + number of cows = 40

for x>12

number of cows = 40 -x

x > 12

-x < -12

adding 40 both sides

40-x < 40-12

number of cows <28