one million two billion three hundred thousand fortytwo

one million

two billion three hundred thousand

forty-two hundredths

one hundred fifty-two millionths

two million three hundred thirty-five thousand sixty-seven hundredths

Rounding (+) Numbers 1. Identify the place to which you are rounding.

Rounding (+) Numbers 2. 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 (+) Numbers 3. Change all digits to the right of the rounding place to zeros.

Example 1 Round 7, 384 to each indicated place. thousand: 7, 000

Example 1 Round 7, 384 to each indicated place. hundred: 7, 400

Example 1 Round 7, 384 to each indicated place. ten: 7, 380

Example 2 Round 15, 469. 7482 to each indicated place. tenth: 15, 469. 7

Example 2 Round 15, 469. 7482 to each indicated place. ten thousand: 20, 000

Example 2 Round 15, 469. 7482 to each indicated place. hundredth: 15, 469. 75

Example 3 Estimate the sum of 17, 436 + 43, 519 by rounding each addend to its highest place value. 60, 000

Example 4 Estimate the difference of 60. 09241 – 3. 0483 by rounding each addend to the nearest hundredth. 57. 04

Example 5 Estimate the product by rounding. 42 • 87 3, 600

Example 5 Estimate the product by rounding. 942 • 78 72, 000

Example 6 Estimate the quotient by rounding. 263 ÷ 9 30

Example 6 Estimate the quotient by rounding. 1, 149 ÷ 34 40

Example 7 Estimate the sum of 373 + 224 using front-end estimation. Then adjust the answer to get a more accurate estimate.

Example 8 Estimate the difference of 34, 289 − 18, 192 using frontend estimation. Adjust to get a more accurate estimate.

Example Round to the nearest ten. 847 850

Example Round to the nearest ten. 32, 425 32, 430

Example Round to the nearest hundred. 54, 941 54, 900

Example Round to the nearest hundred. 16, 990 17, 000

Example Estimate by rounding to the highest place value. 92 + 48 140

Example Estimate by rounding to the highest place value. 3, 247 − 1, 927 1, 000

Example Estimate by rounding to the highest place value. 249 × 792 160, 000

Example Estimate by rounding to the highest place value. 4, 129 ÷ 19 200

Example Estimate by rounding to the highest place value. 347 ÷ 6 50

Example Estimate by rounding to the highest place value. 42, 921 − 8, 416 32, 000

Exercise 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.

Exercise 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

Exercise 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

Exercise 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.