A faraway planet is populated by creatures called Jolos. All Jolos are either green or purple and either one-headed or two-headed.
Balan, who lives on this planet, does a survey and finds that her colony of 140
contains 30 green, one-headed Jolos; 45 purple, two-headed Jolos; and 75
one-headed Jolos.
One-headed Two-headed Total
Green
30
Purple
45
Total
75
140
How many green Jolos are there in Balan's colony?
A. 20
B. 65
O O
C. 50