Envision Math Grade 5 Answer Key Topic 2.2 Rounding Whole Numbers and Decimals

Envision Math 5th Grade Textbook Answer Key Topic 2.2 Rounding Whole Numbers and Decimals

How can you round whole numbers and decimals?
Rounding replaces one number with another number that tells about how many or how much. Round 634 to the nearest hundred.

Another Example

How do you round 2.36 to the nearest tenth? Is 2.36 closer to 2.3 or 2.4?
Think Is 2.36 closer to 2.3 or 2.4?

Step 1
Find the rounding place. Look at the digit to the right of the rounding place.
2.36

Step 2
If the digit is 5 or greater, add 1 to the rounding digit. If the digit is less than 5, leave the rounding digit alone.
Since 6 > 5,
add 1 to the 3.

Step 3
Drop the digits to the right of the rounding digit.
2.36 rounds to 2.4

Guided Practice*

Do you know HOW?

In 1 through 6, round each number to the place of the underlined digit.

Question 1.
16
Answer:

Question 2.
56.1
Answer:

Question 3.
1.32
Answer:

Question 4.
427,841
Answer:

Question 5.
1,652
Answer:

Question 6.
582,062
Answer:

Do you UNDERSTAND?

Question 7.
To round 7,458 to the nearest hundred, which digit do you look at? What is 7,458 rounded to the nearest hundred?
Answer:

Question 8.
A runner is running on a track with markers every 10 meters. If the runner has run 368 meters, is she closer to the 360-meter marker or
the 370-meter marker?
Answer:

Step 1
Find the digit in the rounding place. Underline this digit.
634

Step 2
Look at the digit to the right of the rounding place. If this digit is 5 or greater, add 1 to the rounding digit. If the digit is less than 5, leave the rounding digit alone.

Leave 6 the same

Step 3
Change all the digits to the right of the rounding digit to zeros.
634 rounds to 600.

Independent Practice

In 9 through 16, round each whole number to the place of the underlined digit.

Question 9.
677
Answer:

Question 10.
4,526
Answer:

Question 11.
12,064
Answer:

Question 12.
573
Answer:

Question 13.
34,739
Answer:

Question 14.
59,304
Answer:

Question 15.
930,998
Answer:

Question 16.
748,397
Answer:

In 17 through 24, round each number to the place of the underlined digit.

Question 17.
75.8
Answer:

Question 18.
0.758
Answer:

Question 19.
643.82
Answer:

Question 20.
0.472
Answer:

Question 21.
84.732
Answer:

Question 22.
738.29
Answer:

Question 23.
5.028
Answer:

Question 24.
23.009
Answer:

Problem Solving

Question 25.
The world’s largest aloha shirt is 4.26 meters around the chest. Round 4.26 to the nearest ones place and nearest tenths place.
Answer:

Question 26.
In the first 3 quarters of a basketball game, a team scored 17, 25, and 13 points. Their final score was 75. How many points did the team score in the fourth quarter?
Answer:

Question 27.
An African Watusi steer’s horn measures 95.25 cm around. What is 95.25 when rounded to the nearest tenth? Nearest whole number? Nearest ten?
Answer:

Question 28.
In a recent year, the population of Illinois was 12,653,544. What is that population when rounded to the nearest million?
A. 10,000,000
B. 12,000,000
C. 12,600,000
D. 13,000,000
Answer:

Question 29.
The world land speed record set on October 15, 1997, was 763.03 miles per hour. What is this speed rounded to the nearest ones place?
Answer: