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 :

Sure, let's solve this problem step by step.

1. Let [tex]\( n \)[/tex] be the unknown number.

2. According to the problem, "a number [tex]\( n \)[/tex] is added to 15 less than 3 times itself."

We can break this down as:
- "3 times itself" can be written as [tex]\( 3n \)[/tex].
- "15 less than 3 times itself" can be written as [tex]\( 3n - 15 \)[/tex].

3. When we add [tex]\( n \)[/tex] to [tex]\( 3n - 15 \)[/tex], it should equal 101. So, our equation is:
[tex]\[
n + (3n - 15) = 101
\][/tex]

4. Now, simplify this equation:
[tex]\[
n + 3n - 15 = 101
\][/tex]

5. Combine the like terms:
[tex]\[
4n - 15 = 101
\][/tex]

6. To isolate [tex]\( n \)[/tex], add 15 to both sides of the equation:
[tex]\[
4n - 15 + 15 = 101 + 15
\][/tex]
[tex]\[
4n = 116
\][/tex]

7. Divide both sides by 4:
[tex]\[
n = \frac{116}{4}
\][/tex]
[tex]\[
n = 29
\][/tex]

So, the equation used to find the value of [tex]\( n \)[/tex] is:
[tex]\[
3n - 15 + n = 101
\][/tex]

Thus, the correct choice from the given options is:
[tex]\[
3n - 15 + n = 101
\][/tex]