Samantha is baking cookies for a school fundraiser. She needs to mix different amounts of chocolate chips into her cookie dough. She first adds 3/4 cup of chocolate chips to the dough. Later, she decides to add an additional 2/5 cup of chocolate chips to make the cookies extra chocolatey. How many cups of chocolate chips does Samantha use in total for her cookie dough? HINT: When you need to combine mixed fractions for a total, you may need to change the denominators so that you can then work with the fractions. ***This is a multiple point question. To receive all of your points you will have to show ALL of your work. You will receive a score on this problem after your teacher grades it. 1 point for showing the equation you used to solve this problem. 1 point for showing the common denominator that you found to solve this problem. 1 point for writing the correct answer WITH label. 1 point for explaining/showing all of your work. 4 points total for this problem (4 points) 0 / 10000 Word Limit Skip to navigation

To determine the total amount of chocolate chips Samantha used, we first need to add the two fractions representing the amounts of chocolate chips she added.

1. **Equation**:
The equation to find the total amount of chocolate chips Samantha used is:
\[ \frac{3}{4} + \frac{2}{5} \]

2. **Finding a Common Denominator**:
To add the fractions, we need to find a common denominator. The denominators are 4 and 5. The least common multiple (LCM) of 4 and 5 is 20.
So, we will convert each fraction to have a denominator of 20.

- For \(\frac{3}{4}\):
\[
\frac{3}{4} = \frac{3 \times 5}{4 \times 5} = \frac{15}{20}
\]
- For \(\frac{2}{5}\):
\[
\frac{2}{5} = \frac{2 \times 4}{5 \times 4} = \frac{8}{20}
\]

3. **Adding the Converted Fractions**:
Now we can add the two fractions:
\[
\frac{15}{20} + \frac{8}{20} = \frac{15 + 8}{20} = \frac{23}{20}
\]

4. **Writing the Correct Answer with Label**:
The total amount of chocolate chips Samantha used is:
\(\frac{23}{20}\) cups, or in a mixed number form, it is \(1 \frac{3}{20}\) cups of chocolate chips.

5. **Work Explanation**:
- We began with the initial amounts of chocolate chips: \(\frac{3}{4}\) and \(\frac{2}{5}\).
- We found a common denominator of 20.
- We converted the fractions to have the same denominator:
- \(\frac{3}{4}\) became \(\frac{15}{20}\).
- \(\frac{2}{5}\) became \(\frac{8}{20}\).
- Then we added the fractions in their new form to get \(\frac{23}{20}\).
- Finally, we expressed our final answer as "1 \(\frac{3}{20}\) cups" or simply \(\frac{23}{20}\) cups.

**Final Answer**:
Samantha used a total of **1 \(\frac{3}{20}\) cups of chocolate chips** or **\(\frac{23}{20}\) cups of chocolate chips**.