one millionone million
two billion three hundred thousand
two billion three hundred thousand
forty-two hundredthsforty-two hundredths
one hundred fifty-two millionths
one hundred fifty-two millionths
two million three hundred
thirty-five thousand and sixty-seven
hundredths
two million three hundred
thirty-five thousand and sixty-seven
hundredths
Rounding (+) NumbersRounding (+) Numbers1. Identify the place to which
you are rounding.
Rounding (+) NumbersRounding (+) Numbers2. Look at the digit to the
right of the place to which you are rounding. If it is 5 or greater,
increase the place to which you are rounding by 1.
If it is less than 5, do not change the digit.
Rounding (+) NumbersRounding (+) Numbers3. Change all digits to the
right of the rounding place to zeros.
Round 7,384 to each indicated place.Round 7,384 to each indicated place.
Example 1Example 1
7,0007,000thousand:thousand:
Round 7,384 to each indicated place.Round 7,384 to each indicated place.
7,4007,400hundred:hundred:
Example 1Example 1
Round 7,384 to each indicated place.Round 7,384 to each indicated place.
7,3807,380ten:ten:
Example 1Example 1
Round 15,469.7482 to each indicated place.Round 15,469.7482 to each indicated place.
15,469.715,469.7tenth:tenth:
Example 2Example 2
Round 15,469.7482 to each indicated place.Round 15,469.7482 to each indicated place.
20,00020,000ten thousand:ten thousand:
Example 2Example 2
Round 15,469.7482 to each indicated place.Round 15,469.7482 to each indicated place.
15,469.7515,469.75hundredth:hundredth:
Example 2Example 2
Estimate the sum of 17,436 + 43,519 by rounding each addend to its highest place value.
Estimate the sum of 17,436 + 43,519 by rounding each addend to its highest place value.
60,00060,000
Example 3Example 3
Estimate the difference of 60.09241 – 3.0483 by rounding each addend to the nearest hundredth.
Estimate the difference of 60.09241 – 3.0483 by rounding each addend to the nearest hundredth.
57.0457.04
Example 4Example 4
Estimate the product by rounding.Estimate the product by rounding.
3,6003,60042 • 8742 • 87
Example 5Example 5
Estimate the product by rounding.Estimate the product by rounding.
72,00072,000942 • 78942 • 78
Example 5Example 5
Estimate the quotient by rounding.Estimate the quotient by rounding.
3030263 ÷ 9263 ÷ 9
Example 6Example 6
Estimate the quotient by rounding.Estimate the quotient by rounding.
40401,149 ÷ 341,149 ÷ 34
Example 6Example 6
Estimate the sum of 373 + 224 using front-end estimation. Then adjust the answer to get a more accurate estimate.
Estimate the sum of 373 + 224 using front-end estimation. Then adjust the answer to get a more accurate estimate.
Example 7Example 7
Estimate the difference of 34,289 − 18,192 using front-end estimation. Adjust to get a more accurate estimate.
Estimate the difference of 34,289 − 18,192 using front-end estimation. Adjust to get a more accurate estimate.
Example 8Example 8
Round to the nearest ten.Round to the nearest ten.
850850847847
ExampleExample
Round to the nearest ten.Round to the nearest ten.
32,43032,43032,42532,425
ExampleExample
Round to the nearest hundred.Round to the nearest hundred.
54,90054,90054,94154,941
ExampleExample
Round to the nearest hundred.Round to the nearest hundred.
17,00017,00016,99016,990
ExampleExample
Estimate by rounding to the highest place value.Estimate by rounding to the highest place value.
14014092 + 4892 + 48
ExampleExample
Estimate by rounding to the highest place value.Estimate by rounding to the highest place value.
1,0001,0003,247 − 1,9273,247 − 1,927
ExampleExample
Estimate by rounding to the highest place value.Estimate by rounding to the highest place value.
160,000160,000249 × 792249 × 792
ExampleExample
Estimate by rounding to the highest place value.Estimate by rounding to the highest place value.
2002004,129 ÷ 194,129 ÷ 19
ExampleExample
Estimate by rounding to the highest place value.Estimate by rounding to the highest place value.
5050347 ÷ 6347 ÷ 6
ExampleExample
Estimate by rounding to the highest place value.Estimate by rounding to the highest place value.
32,00032,00042,921 − 8,41642,921 − 8,416
ExampleExample
Mr. Brown drove his new car for 76,845 mi. He sold the car to his brother, who drove it for 34,923 mi. Estimate the total mileage to the nearest thousand miles.
Mr. Brown drove his new car for 76,845 mi. He sold the car to his brother, who drove it for 34,923 mi. Estimate the total mileage to the nearest thousand miles.
112,000 mi.112,000 mi.
ExerciseExercise
Mr. Wilson bought a new car for $19,875. He later sold the car for $9,495. Estimate the difference to the nearest hundred dollars.
Mr. Wilson bought a new car for $19,875. He later sold the car for $9,495. Estimate the difference to the nearest hundred dollars.
$10,400$10,400
ExerciseExercise
Mr. Ricks test-drove a car that was on sale for $15,990. He asked the dealer to add optional equipment costing $899. Estimate the total cost to the nearest hundred dollars.
Mr. Ricks test-drove a car that was on sale for $15,990. He asked the dealer to add optional equipment costing $899. Estimate the total cost to the nearest hundred dollars. $16,900$16,900
ExerciseExercise
Use front-end estimation to estimate the total cost of Jesselyn’s lunch. Then give a more accurate estimate. She purchased a cheeseburger for $3.59, french fries for $1.44, a fruit cup for $1.39, and a soft drink for $0.99.
Use front-end estimation to estimate the total cost of Jesselyn’s lunch. Then give a more accurate estimate. She purchased a cheeseburger for $3.59, french fries for $1.44, a fruit cup for $1.39, and a soft drink for $0.99.
ExerciseExercise