College

A number, [tex]n[/tex], is added to 15 less than 3 times itself. The result is 101. Which equation can be used to find the value of [tex]n[/tex]?

A. [tex]3n - 15 + n = 101[/tex]

B. [tex]3n + 15 + n = 101[/tex]

C. [tex]3n - 15 - n = 101[/tex]

D. [tex]3n + 15 - n = 101[/tex]

Answer :

To solve this problem, let's break down the steps:

1. Understand the problem: We want to find a number [tex]\( n \)[/tex] such that when it is added to 15 less than 3 times itself, the result is 101.

2. Translate the problem into an equation:
- "3 times itself" can be written as [tex]\( 3n \)[/tex].
- "15 less than 3 times itself" is [tex]\( 3n - 15 \)[/tex].
- The sum of [tex]\( n \)[/tex] and "15 less than 3 times itself" is [tex]\( n + (3n - 15) \)[/tex].

3. Set up the equation:
[tex]\[
n + (3n - 15) = 101
\][/tex]

4. Simplify the equation:
- Combine like terms:
[tex]\[
n + 3n - 15 = 101
\][/tex]
[tex]\[
4n - 15 = 101
\][/tex]

5. Solve for [tex]\( n \)[/tex]:
- Add 15 to both sides of the equation:
[tex]\[
4n - 15 + 15 = 101 + 15
\][/tex]
[tex]\[
4n = 116
\][/tex]
- Divide both sides by 4:
[tex]\[
n = \frac{116}{4}
\][/tex]
[tex]\[
n = 29
\][/tex]

6. Verify the solution: Plug [tex]\( n = 29 \)[/tex] back into the context of the original problem:
- Calculate 3 times 29: [tex]\( 3 \times 29 = 87 \)[/tex]
- Calculate 15 less than that: [tex]\( 87 - 15 = 72 \)[/tex]
- Now add 29 to that result: [tex]\( 29 + 72 = 101 \)[/tex], which satisfies the original condition.

Therefore, the correct equation from the choices given is:

[tex]\[ 3n - 15 + n = 101 \][/tex]

And the value of [tex]\( n \)[/tex] is 29.