80=6th graders
40=5th graders
80+40=120
120/22= 60/11
120/25=24/5
120/30= 4
There are 30 students in each class because he teaches 4 class and 120/30 will give you 4.
The answer to 84 divided by 4=21.
Answer:
Step-by-step explanation:
Simplifying
3.4 + 2(9.7 + -4.8x) = 61.2
3.4 + (9.7 * 2 + -4.8x * 2) = 61.2
3.4 + (19.4 + -9.6x) = 61.2
Combine like terms: 3.4 + 19.4 = 22.8
22.8 + -9.6x = 61.2
Solving
22.8 + -9.6x = 61.2
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '-22.8' to each side of the equation.
22.8 + -22.8 + -9.6x = 61.2 + -22.8
Combine like terms: 22.8 + -22.8 = 0.0
0.0 + -9.6x = 61.2 + -22.8
-9.6x = 61.2 + -22.8
Combine like terms: 61.2 + -22.8 = 38.4
-9.6x = 38.4
Divide each side by '-9.6'.
x = -4
Simplifying
x = -4
W = 21 - 3
weight of the tree = 21 pounds - 3 pounds