[25 points] Help with proportions, I don't understand! 134 out of 205 families in "Chimgan" village keep cows, 142 keep sheep and 76 keep goats. 67 families have cows and sheep, 10 have cows and goats, 15 have sheep and goats. There are 34 families who keep all three kinds of pets. a) How many families keep only one kind of pet?
b) How many have no pets at all? Hint: Use the following diagram.
