Answer:
30
Step-by-step explanation:
20+11=31
It can't be exactly 31 but it can be any number less than 31, so the nearest whole number down is 30
AnsWER:
shaded: 40% unshaded 60%
ONLY 4 ROWS ARE SHADED
non shaded are 6 rows
10 rows in total
-7
4448.23