Math · Age 10 · Addition & Subtraction
Efficient Calculation Strategies (Ex. 1)
Choose efficient mental or written strategies depending on the problem.
Module
Addition & Subtraction
Age
Age 10
Duration
8 min
Questions
5
What's in this exercise
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Question 1
Multiple choice
What is the most efficient way to calculate 998 + 456?
Question 2
Multiple choice
4,999 + 3,001 = ?
Question 3
Multiple choice
The quickest way to calculate 500,000 - 499,998 is to:
Question 4
Sequence
What is the missing number in the sequence? 100 ; 200 ; 400 ; ___ ; 1,600
Question 5
True or false
750 + 250 is easy to calculate mentally because they make a round number.