Estimation & Checking Answers (Ex. 1)

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1. Question 1

   Multiple choice

   Estimate 3,876 + 5,124 by rounding to the nearest thousand.

2. Question 2

   Multiple choice

   To check 6,543,210 − 2,345,678 = 4,197,532, you should calculate:

3. Question 3

   Multiple choice

   A student gets the answer 13,000,000 for 7,432,100 + 4,987,900. Is this reasonable?

4. Question 4

   Sequence

   Using inverse to check: if 5,000,000 − 2,345,678 = 2,654,322, then 2,654,322 + 2,345,678 = ___.

5. Question 5

   True or false

   Rounding both numbers before adding gives an estimate, not an exact answer.

More exercises in this module

• Mental vs Written Methods (Ex. 3)

• Large Addition Across Millions (Ex. 5)

• Large Subtraction from Millions (Ex. 6)

• Mixed Operations with Millions (Ex. 7)

• Six-Digit Addition (Ex. 1)

• Adding & Subtracting Large Integers (Ex. 3)