27. a farmer divides his herd of cows among his
four sons so that first son gets one half of the
berd, the second son one-fourth, the third son
one fifth and the fourth son 7 cows, the total
number of cows in the herd is:

we have to find a common denominator for the fractions so

1/2 1/4 1/5

they all go into 20

so

10/20 5/20 4/20

in total that is 19/20

so the last son has 1/20 which is seven

so 20/20 is 20 times that amount which is 140

140 cows

Step-by-step explanation:

answer: 21$

step-by-step explanation:

$42 / $14 = 3   (ratio 3: 1)

$7 x 3 = $21

answer: for each 3 girls there is 2 boys . 3: 2

hope this ! (:   mark me as brainliest if you can