Estimate differences

Front

What is estimating differences in math?

Back

Estimating differences means finding an approximate answer to a subtraction problem by rounding the numbers first.

Front

How do you round a number to the nearest ten?

Back

Look at the digit in the ones place. If it's 5 or more, round up. If it's 4 or less, round down.

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.A.3

Front

Estimate the difference: 642 - 137. Round to the nearest ten first.

Back

500

Front

What number could round to 80?

Back

78 (because it is closer to 80 than 74 or 88).

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.A.3

Front

Estimate the difference: 71 - 37. Round to the nearest ten first.

Back

30

Front

How do you round a number to the nearest hundred?

Back

Look at the digit in the tens place. If it's 5 or more, round up. If it's 4 or less, round down.

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.A.3

Front

Estimate the difference: 546 - 209. Round to the nearest ten first.

Back

340

Front

What is the estimated difference of 642 - 137 when rounded to the nearest hundred?

Back

500

Front

What is the purpose of estimating in math?

Back

Estimating helps to quickly find an approximate answer without doing exact calculations.

Front

What is the estimated difference of 80 - 45? Round to the nearest ten first.

Back

30