Math in Focus Grade 3 Chapter 2 Practice 5 Answer Key Using Front-End Estimation

by

Go through the Math in Focus Grade 3 Workbook Answer Key Chapter 2 Practice 5 Using Front-End Estimation to finish your assignments.

Math in Focus Grade 3 Chapter 2 Practice 5 Answer Key Using Front-End Estimation

Write the leading digit.

Question 1.
473 ___
Answer:
The leading digit is 4.

Question 2.
801 ___
Answer:
The leading digit is 8.

Question 3.
198 ____
Answer:
The leading digit is 1.

Question 4.
5,147 ___
Answer:
The leading digit is 5.

Question 5.
7,061 ___
Answer:
The leading digit is 7.

Question 6.
9,625 ____
Answer:
The leading digit is 9.

Find the sum. Use front-end estimation to check that each answer is reasonable.

Example
Math in Focus Grade 3 Chapter 2 Practice 5 Answer Key Using Front-End Estimation 1

Question 7.
Find 312 + 526.
Math in Focus Grade 3 Chapter 2 Practice 5 Answer Key Using Front-End Estimation 2
The estimated sum is ___
The answer ___ is reasonable.
Answer:

The estimated sum is 800
The answer is 838 is reasonable

Find the sum. Use front-end estimation to check that each answer is reasonable.

Question 8.
Find 364 + 509.
Math in Focus Grade 3 Chapter 2 Practice 5 Answer Key Using Front-End Estimation 3
The estimated sum is ___
The answer ___ is reasonable.
Answer:

The estimated sum is 900
The answer 873 is reasonable.

Question 9.
Find 286 + 473.
Math in Focus Grade 3 Chapter 2 Practice 5 Answer Key Using Front-End Estimation 4
The estimated sum is ___
The answer ___ is reasonable.
Answer:

The estimated sum is 800
The answer 759 is reasonable.

Find the difference. Use front-end estimation to check that each answer is reasonable.

Example
Math in Focus Grade 3 Chapter 2 Practice 5 Answer Key Using Front-End Estimation 5

Question 10.
Find 618 – 372.
Math in Focus Grade 3 Chapter 2 Practice 5 Answer Key Using Front-End Estimation 6
The estimated difference is ___
The answer ___ is reasonable.
Answer:

The estimated difference is 200
The answer 246 is reasonable.

Question 11.
Find 936 – 528.
Math in Focus Grade 3 Chapter 2 Practice 5 Answer Key Using Front-End Estimation 7
The estimated difference is ___
The answer ___ is reasonable.
Answer:

The estimated difference is 400
The answer 408 is reasonable.

Question 12.
Find 759 – 236.
Math in Focus Grade 3 Chapter 2 Practice 5 Answer Key Using Front-End Estimation 8
The estimated difference is ___
The answer ___ is reasonable.
Answer:

The estimated difference is 600
The answer 523 is not reasonable.

Solve.

Question 13.
The length of a train engine is 439 centimeters. The length of the carriage is about 558 centimeters. Estimate the total length of the train and the carriage.
Math in Focus Grade 3 Chapter 2 Practice 5 Answer Key Using Front-End Estimation 9
Answer:
Given,
The length of a train engine is 439 centimeters. The length of the carriage is about 558 centimeters.
439 is near to 400 and 558 is near to 600.
So, 400 + 600 = 1000
Therefore, the Estimation of the total length of the train and the carriage is 1000 centimeters.

Question 14.
A wooden pole is 356 centimeters long. 104 centimeters of it is driven into the ground. About what height of the wooden pole is above the ground?
Math in Focus Grade 3 Chapter 2 Practice 5 Answer Key Using Front-End Estimation 10
Answer:
Given,
A wooden pole is 356 centimeters long. 104 centimeters of it is driven into the ground.
356 is near to 400 and 104 is near to 100
So, 400 – 100 = 300
Therefore, approximately 300 centimeters of the wooden pole is above ground.

Leave a Comment