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

Answer 1

To find the total amount of chocolate chips Samantha uses, we need to add the two amounts together: \( \frac{3}{4} \) cup and \( \frac{2}{5} \) cup.

To add these fractions, we need a common denominator. The denominators here are 4 and 5. The least common multiple of 4 and 5 is 20.

Next, we will convert each fraction to have the same denominator:

1. For \( \frac{3}{4} \): \[ \frac{3}{4} = \frac{3 \times 5}{4 \times 5} = \frac{15}{20} \]

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

Now we can add the two fractions: \[ \frac{15}{20} + \frac{8}{20} = \frac{15 + 8}{20} = \frac{23}{20} \]

The total amount of chocolate chips used is \( \frac{23}{20} \) cups, which can also be expressed as a mixed number: \[ \frac{23}{20} = 1 \frac{3}{20} \]

Thus, Samantha uses a total of \( \frac{23}{20} \) cups of chocolate chips, or \( 1 \frac{3}{20} \) cups when expressed as a mixed number.