Chapter 3: Q. 22 (page 315)

In the following exercises, solve each number word
The difference of four times a number and seven is $21$ . Find the number.

Short Answer

Expert verified

The number is $7$ .

Step by step solution

Step 1. Given Information

We are given that the difference of four times a number and seven is $21$ .

We have to find the number.

Step 2. Forming the equation

Let the number bex,

So, the equation will be,

$4 x - 7 = 21$

Step 3. Solving the equation

Adding $7$ from both sides, we get

$4 x - 7 = 21 4 x = 21 + 7 4 x = 28$

Dividing by $4$ ,

$x = \frac{28}{4} x = 7$

Hence, the number is $7$ .

Step 4. Checking the solution

Putting the value of xin the equation, we get

$4 x - 7 = 21 4 (7) - 7 = 21 28 - 7 = 21 21 = 21 L H S = R H S$

Hence the solution is correct.

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In the following exercises, solve each number word
The difference of four times a number and seven is $21$ . Find the number.

Short Answer

Step by step solution

Step 1. Given Information

Step 2. Forming the equation

Step 3. Solving the equation

Step 4. Checking the solution

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In the following exercises, solve each number wordThe difference of four times a number and seven is 21. Find the number.

Short Answer

Step by step solution

Step 1. Given Information

Step 2. Forming the equation

Step 3. Solving the equation

Step 4. Checking the solution

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Math Textbooks

Pure Maths

Mechanics Maths

Decision Maths

Statistics

Logic and Functions

Probability and Statistics

Study anywhere. Anytime. Across all devices.

In the following exercises, solve each number word
The difference of four times a number and seven is $21$ . Find the number.