Question

1. brad used the compatible numbers 520 ÷ 20 for an estimate. which quotient might he be finding? a 5,380 ÷ 59 522 ÷ 21 c 477 ÷ 31 d 84 ÷ 9

Explanation:

Step1: Recall compatible numbers

Compatible numbers are numbers that are easy to compute with mentally. For division, we look for numbers close to the original dividend and divisor that form a simple division. Brad used \(520\div20\), so we need to check which option has a dividend close to 520 and a divisor close to 20.

Step2: Analyze Option A

For \(5380\div59\), the dividend is 5380 (much larger than 520) and divisor is 59 (not close to 20). So this is not a match.

Step3: Analyze Option B

For \(522\div21\), the dividend 522 is close to 520, and the divisor 21 is close to 20. So this is a good candidate for using \(520\div20\) as a compatible number estimate.

Step4: Analyze Option C

For \(477\div31\), the dividend 477 is not close to 520, and the divisor 31 is not close to 20. So this is not a match.

Step5: Analyze Option D

For \(84\div9\), the dividend 84 is not close to 520, and the divisor 9 is not close to 20. So this is not a match.

Answer:

B. \(522\div21\)