Estimate Decimal Quotients Using Compatible Numbers
To estimate decimal quotients, round the dividend and divisor to compatible numbers that are easy to divide mentally using basic facts. Compatible numbers are close to the original values but produce simpler calculations. This Grade 5 math skill from Eureka Math Chapter 13 covers partial quotients and multi-digit decimal division estimation.
Key Concepts
To estimate a decimal quotient, round the dividend and divisor to compatible numbers. Compatible numbers are numbers that are close to the original numbers and are easy to compute with mentally, often using basic facts. $$Original \ Problem \approx Rounded \ Problem = Estimate$$.
Common Questions
How do you estimate a decimal quotient?
Round both the dividend and divisor to compatible numbers that are easy to divide using basic facts, then perform the simpler division to get an approximate answer.
What are compatible numbers?
Compatible numbers are numbers close to the original values that are easy to compute mentally, such as rounding 39.1 to 40 and 17 to 20 to make the estimation 40 divided by 20 equals 2.
Why is estimating quotients useful?
Estimating quotients helps you check the reasonableness of your exact answer and verify that you have placed the decimal point correctly in the actual quotient.
What is an example of estimating 3.91 divided by 17?
Round 3.91 to approximately 4 and 17 to approximately 20. Then estimate 4 divided by 20 equals 0.2, so 3.91 divided by 17 is approximately 0.2.