There were160 eggs 13/32 was sold in AM. 2/5 of the rest were sold in PM. How many eggs were in PM?

Question

A had 3 1/3 kg of nuts. A gave 1/6 of nuts to B. How many more kgs of nuts did A have than B?

A roll of ribbon is 1 1/3 m in length. If each metre costs $12 3/5, how much money will be left if Mum buys 2 rolls of ribbon with $40?

Answer 1

For the first one, if you sold 13/32 of 160, then you have 19/32 left. 19/32 of 160 is found by just multiplying the two - you end up with 95. Then, if you sold 2/5 later on, you have 3/5 left. 3/5 of 95 is found the same way - through multiplying. So, 3/5 of 95 is 57.

For the second one, if A had 3 1/3 kg of nuts and gave away 1/6 of his stash, you're multiplying again. 3 1/3 = 10/3 in improper form (it's easier to work with improper fractions when multiplying). If you gave away 1/6, you have 5/6 left, and 5/6 of 10/3 = 25/9, or 2 7/9 kg.

For the last one, if you have 1 1/3 m of ribbon, you have 4/3 m. If each costs $12 3/5, you may be better off converting this to currency. 3/5 is 0.60, so you're really talking about $12.60. So, we have 2 rolls of ribbon, for a total of 8/3 m, and each meter costs $12.60, so you have $33.60 worth of ribbon. And if mum has $40, she'll have $6.40 left over.

The key in all of these problems is to recognize that whenever something is "of" something else, like "1/6 of 3 1/3" it means to multiply the two numbers.