# McGraw Hill Math Grade 4 Chapter 10 Lesson 9 Answer Key Problem Solving: Using Formulas

Practice the questions of McGraw Hill Math Grade 4 Answer Key PDF Chapter 10 Lesson 9 Problem Solving: Using Formulas to secure good marks & knowledge in the exams.

## McGraw-Hill Math Grade 4 Answer Key Chapter 10 Lesson 9 Problem Solving: Using Formulas

Solve

Question 1.
Mr. Smith wants to build a fence around his backyard. It is square-shaped and measures 7 meters on one side. How many meters of fence will Mr. Smith need to build?
(2 Ã— 7) + (2 Ã— 7) = 28m

Explanation:
Mr. Smith wants to build a fence around his backyard
It is square-shaped and measures 7 meters on one side
Perimeter of a square = (2 x l) + (2 x w)
That is (2 Ã— 7) + (2 Ã— 7)
= 14 + 14
= 28
So, Mr. Smith need 28 m to build the fence.

Question 2.
Gary builds a rectangular rabbit pen. The pen measures 6 feet by 8 feet. How many square feet is the pen?
48 square feet

Explanation:
Gary builds a rectangular rabbit pen
The pen measures 6 feet by 8 feet
Area of a rectangle = l x w
Length of the pen is 6 feet
Width of the pen is 8 feet
Area – l x w = 6 x 8 = 48 feet
So, the area of the rectangular pen is 48 square feet.

Question 3.
The town of Grand Sun marks off a large rectangular patch of land as a forest preserve. The land measures 14 kilometers long and 8 kilometers wide. What is the total area of the forest preserve?