High School

Select the equation needed to solve the following word problem:

Kayla is sending invitations to 20 of her friends for a pizza party. If there are 12 invitations left to send out, how many invitations has she already mailed?

A. [tex]x + 8 = 12[/tex]

B. [tex]x + 20 = 12[/tex]

C. [tex]x + 12 = 20[/tex]

D. [tex]x - 8 = 20[/tex]

Answer :

To solve the word problem, let's break it down step-by-step.

Problem:
Kayla is sending invitations to 20 of her friends for a pizza party. If there are 12 invitations left to send out, how many invitations has she already mailed?

To find the number of invitations Kayla has already mailed, we need to use the following information:
- Total invitations Kayla plans to send: 20
- Invitations left to send out: 12

Let's denote the number of invitations Kayla has already mailed as [tex]\( x \)[/tex].

We can set up the following equation based on the given information:
[tex]\[ \text{Total invitations} = \text{Invitations already mailed} + \text{Invitations left to send out} \][/tex]

In mathematical terms, this can be written as:
[tex]\[ 20 = x + 12 \][/tex]

To find [tex]\( x \)[/tex], we need to isolate it on one side of the equation:
[tex]\[ x + 12 = 20 \][/tex]

Subtract 12 from both sides of the equation:
[tex]\[ x = 20 - 12 \][/tex]

So,
[tex]\[ x = 8 \][/tex]

This means Kayla has already mailed 8 invitations.

The correct equation needed to solve the word problem is:
[tex]\[ C. \, x + 12 = 20 \][/tex]