Question

What is the sum of 9/10+3/8​?
Responses

1 9/40
1 and 9 over 40

21/40
21 over 40

1 11/40
1 and 11 over 40

3/20

Answer 1

To calculate the sum of \( \frac{9}{10} + \frac{3}{8} \), we first need a common denominator.

The least common multiple (LCM) of 10 and 8 is 40.

Now, we can convert both fractions to have a denominator of 40:

1. Convert \( \frac{9}{10} \):
\[
\frac{9}{10} = \frac{9 \times 4}{10 \times 4} = \frac{36}{40}
\]

2. Convert \( \frac{3}{8} \):
\[
\frac{3}{8} = \frac{3 \times 5}{8 \times 5} = \frac{15}{40}
\]

Now we can sum the two fractions:
\[
\frac{36}{40} + \frac{15}{40} = \frac{36 + 15}{40} = \frac{51}{40}
\]

Next, we can convert \( \frac{51}{40} \) into a mixed number:
\[
\frac{51}{40} = 1 \frac{11}{40}
\]

So, the final answer is:
**1 and 11 over 40** or **\( \frac{51}{40} \)**.

The appropriate response from your options is:
**1 11/40**.