Chapter 1: Q3. (page 3)

Find each sum or difference.
$20 + (- 7)$

Short Answer

Expert verified

The value of expression is 13.

Step by step solution

Step 1. Apply the concept of addition and subtraction.

Two numbers with similar signs get added and the resulting number carries the similar sign.

Two numbers with opposite signs get subtracted and the resulting number carries the sign of the larger number.

Step 2. Concept of like and unlike signs.

If there is a sign like $+ (+)$ or $- (-)$ then the resulting sign will be positive and if there is an unlike sign $+ (-)$ or $- (+)$ then the resulting sign will be negative.

So, the given sum can be written as

$\begin{array}{l} = 20 + (- 7) \\ = 20 - 7 \end{array}$

Step 3. Evaluate the expression.

Now, subtract the numbers to get

$\begin{array}{l} = 20 - 7 \\ = 13 \end{array}$

Therefore the sum is 13.

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Find each sum or difference.
$20 + (- 7)$

Short Answer

Step by step solution

Step 1. Apply the concept of addition and subtraction.

Step 2. Concept of like and unlike signs.

Step 3. Evaluate the expression.

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Find each sum or difference.20+−7

Short Answer

Step by step solution

Step 1. Apply the concept of addition and subtraction.

Step 2. Concept of like and unlike signs.

Step 3. Evaluate the expression.

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Math Textbooks

Discrete Mathematics

Applied Mathematics

Calculus

Geometry

Decision Maths

Mechanics Maths

Study anywhere. Anytime. Across all devices.

Find each sum or difference.
$20 + (- 7)$