C. Estimate the answers to the following questions using rounding method. Choose the letter of the correct answer.
7. About how many 21s are there in 6,189?
b. 15,000 a. 300 c. 150,000

8. About how many 52s are there in 1,844?
b. 50 a. 40 c. 60

9. About how many dozens are there in 214 pieces?
b. 30 a. 20 c. 40​