College

Select the correct answer.

The sum of two consecutive numbers is 157. This equation, where [tex]n[/tex] is the first number, represents the situation: [tex]2n + 1 = 157[/tex].

What is the first number?

A. 77
B. 78
C. 79
D. 80

Answer :

Let's solve the problem step by step:

We need to find two consecutive numbers whose sum is 157. Let's say the first number is [tex]\( n \)[/tex].

Since the numbers are consecutive, the second number will be [tex]\( n + 1 \)[/tex].

According to the problem:
[tex]\[ n + (n + 1) = 157 \][/tex]

This simplifies to:
[tex]\[ 2n + 1 = 157 \][/tex]

Now, let's solve for [tex]\( n \)[/tex]:

1. Subtract 1 from both sides of the equation:
[tex]\[ 2n = 157 - 1 \][/tex]
[tex]\[ 2n = 156 \][/tex]

2. Divide both sides by 2:
[tex]\[ n = \frac{156}{2} \][/tex]
[tex]\[ n = 78 \][/tex]

So, the first number is 78.

Therefore, the correct answer is:
B. 78