First of all, we know that a nickel is worth 5 cents, and a penny is worth 1 cent. Let's figure out how many cents in nickels Paula has first.
We know she has 7 nickels, and each of them are worth 5 cents.
7 x 5 = 35.
Now that we know the value of Paula's nickels, let's figure out how many pennies she has left. Let's subtract the 7 nickels from the total 24 coins Paula has.
24 - 7 = 17.
Now that we know she has 17 pennies left, we know that each penny is worth a cent, so she has 17 cents worth of pennies. Let's add the 17 cents of pennies to the 35 cents of nickels.
17 + 35 = 52.
There you have it, Paula has a total of 52 cents in her drawer.
Hope this helped you out. :)