Mr. Free's science class measures rain for two months. In the first month, there was 3 of an inch of rain. In the second month, there was & of an inch of rain. What was the total amount of rain over the two months? How much would it have to rain in the third month to reach " of an inch for all three months?

To find the total amount of rain over the two months, you need to add the amount of rain in the first month to the amount of rain in the second month:

Amount of rain in the first month = 3 inches

Amount of rain in the second month = 4/3 inches

Total amount of rain over two months = 3 inches + 4/3 inches

To add these two amounts, you'll need a common denominator. The common denominator of 3 and 3 is 3. So, rewrite the fractions with a common denominator:

Total amount of rain over two months = (3*3/3) inches + (4/3) inches

= (9/3) inches + (4/3) inches

= 13/3 inches

Now, to find out how much it would have to rain in the third month to reach 5/3 inches for all three months, subtract the total amount of rain received in the first two months from 5/3 inches:

Amount of rain needed in the third month = 5/3 inches - 13/3 inches

= (5 - 13)/3 inches

= (-8/3) inches

So, it would need to rain -8/3 inches in the third month to reach 5/3 inches for all three months. This means it would have to rain 2 and 2/3 inches in the third month.