Beth needs 1 2/3 cups of sugar to make a cake and 2 1/4 cups to make a pie. How much sugar does she need to make both?

you are adding 1 2/3 + 2 1/4

first these are mixed fractions lets change them to regular fractions for 1 2/3 take the whole number and multiply by the denominator 3 and add the numerator, then that number over denominator 3 so

(1 x 3) + 2 = 5/3 do that with 2 1/4

what did you get?

1 2/3 + 2 1/4

5/3+9/4 (to convert them into like fractions we should do LCM of the denominators the lcm of it is 12)

20/12+27/12

47/12

3 11/12 cups of sugar is needed