Karen prepared 9 kilograms of dough after working 3 hours. How many hours did Karen work if she prepared 12 kilograms of dough?

Answer 1

9/3 = 12/x set the ratio of product to hours equal 9 kilos per 3 hours = 12 kilos per x hours

cross multiply

9x =36 divide by 9

x=4

every hour she did 3

for 12 , she worked 4 hours 12/3=4 hours