In this lesson, we will apply our understanding of rounding to the nearest multiples of 10 000 and 1000 to estimate the answer to addition equations.
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Correct answer: Rounding numbers in an equation to provide an approximate answer before calculation.
Rounding numbers in an equation to provide an approximate answer before calculation.
Using decimal numbers in addition equations.
Using whole numbers in addition equations.
Q2.
Round '456 244' to the nearest multiple of 10 000.
400 000
450 000
Correct answer: 460 000
460 000
500 000
Q3.
3. Using rounding to the nearest multiple of 10 000 to estimate the answer to: 341 782 + 456 913 =
300 000 + 500 000 = 800 000
340 000 + 450 000 = 790 000
Correct answer: 340 000 + 460 000 = 800 000
340 000 + 460 000 = 800 000
342 000 + 457 000 = 799 000
Q4.
4. Use rounding to the nearest multiple of 1000 to estimate the answer to: 187 221 + 243 891 =
187 000 + 243 000 = 430 000
Correct answer: 187 000 + 244 000 = 431 000
187 000 + 244 000 = 431 000
190 000 + 240 000 = 430 000
200 000 + 200 000 = 400 000
Q5.
What is one of the problems associated with rounding to estimate?
Rounding to estimate always takes much longer than actually calculating the answer.
Correct answer: Rounding to estimate decreases the accuracy of your answer: your estimated answer will either be greater or less than your actual answer.
Rounding to estimate decreases the accuracy of your answer: your estimated answer will either be greater or less than your actual answer.
Rounding to estimate does not allow you to subtract.
Rounding to estimate makes equations harder to calculate.
Lesson appears in
UnitMaths / Problem solving with integer addition and subtraction