Answer:
SA = 2400 cm²
Step-by-step explanation:
SA of a cube = S² x 6 (the number of its faces)
SA = 20² x 6
SA = 400 x 6
SA = 2400 cm²
Answer:
73%
Step-by-step explanation:
First, you'll divide the total squares by 100 to get how much is one percent. Then, you divide the shaded squares by the value of 1%. And you'll get how many percents are shaded.
For equivalent decimal, you divide the number by 100.
Then for equivalent decimal, you get the percent and 100.

R=xa+xb, r-xa=xb, b=r-xa/x
Solve for x by plugging in y, then plug x back in