Estimating Products Using Compatible Numbers
Estimating Products Using Compatible Numbers (Chapter 3 instance) is a Grade 4 math skill in enVision Mathematics. Students replace a factor with a nearby compatible number to simplify multiplication and produce a reasonable estimate of the product.
Key Concepts
To estimate a product $a \times b$, replace the factors with nearby compatible numbers, $c$ and $d$, such that $c \approx a$ and $d \approx b$. The estimate is the product $c \times d$.
Common Questions
How do you estimate products using compatible numbers in Grade 4?
Replace one factor with a nearby compatible number that is easy to multiply mentally. For example, to estimate 6 times 348, use 6 times 350 equals 2,100.
What makes a number compatible for multiplication?
A number is compatible when it is close to the original and easy to multiply mentally, such as a multiple of 10, 25, or 50.
What is an example of compatible number estimation in Grade 4?
To estimate 7 times 293, use 7 times 300 equals 2,100. The compatible number 300 is close to 293 and a familiar multiple of 100.
How close should a compatible number be to the original?
Choose a compatible number that is as close as possible to the original value to ensure your estimate is reasonable. The closer the compatible number, the better the estimate.
What grade and chapter covers compatible number estimation for multiplication?
This skill is in Grade 4 enVision Mathematics, Chapter 3: Use Strategies and Properties to Multiply by 1-Digit Numbers.