Someone please explain!

Let the number of beads = x

Sum of the ratio = 11

a) fraction of yellow beads :

b) given there are 75 beads , x =75

# of yellow beads =

#of green beads =

Number of green beads = 20

c) After adding more beads.

Given yellow beads = 3 times as many green = 3×20 = 60

Gabby added  more yellow beads.

there were only 2 presidents that were under the age of 45. theodore roosevelt, and jfk, that makes 5%