Mrs. Corbett signed 1/2 of all the holiday cards and Mr. Corbett signed 3/8 of all of them. Mrs. Smith will sign the rest of them. If there were 32 cards in all, how many are left to be signed by Mrs. Smith?

4 cards

Step-by-step explanation:

1. Approach

First, find how much () of all the holiday cards is. Then find out how much of all the cards is. After doing so, subtract both amounts from the total number of holiday cards.

2. Find out how many were signed

To find out how much a fraction of a certain value is, multiply the fraction by the value.

3. Find out how many were left

Now subtract the number of signed cards from the total number of cards.