Question

What value of n makes this equation true?



0.7n + 0.8n = 2.1



Responses

n = 0.60
n = 0.60

n = 1.40
n = 1.40

n = 3.15
n = 3.15

n = 3.60

Answer 1

To solve the equation \(0.7n + 0.8n = 2.1\), we first combine the like terms on the left side:

\[
0.7n + 0.8n = (0.7 + 0.8)n = 1.5n
\]

So, the equation simplifies to:

\[
1.5n = 2.1
\]

Next, we solve for \(n\) by dividing both sides by 1.5:

\[
n = \frac{2.1}{1.5}
\]

Calculating the division:

\[
n = 1.4
\]

The value of \(n\) that makes the equation true is \(n = 1.40\). Thus, the correct response is:

**n = 1.40**