Answer:

Step-by-step explanation:
when solving and equation with a variable, you must work backwards and do the opposite of the equation
sooo… you must subtract 4 (opposite of +4 is -4)

x=12
The greatest number of adults who can chaperone
35-20 = 15
120 = 2³ × 3 × 5
to obtain prime factors
120 ÷ 2 = 60
60 ÷ 2 = 30
30 ÷ 2 = 15
15 ÷ 3 = 5
5 ÷ 5 = 1
prime factors are 2³ × 3 × 5