Now that you've learned so much about subtraction, you can be a subtraction problem solve­r! You may find a lot of things outside the classroom involve subtraction. But these problems are not given to you in columns. They are usually word problems. Most of the time, you have to figure them out yourself. But don't worry, it's very simple. You just need to look at the word problem carefully and figure out each part.

Take a look at this problem:

Carol slept 2 hours longer than Diane. Diane slept for 7 hours. How long did Carol sleep?

How do we determine the number family? The first sentence tells which person is the greatest (larger) number. Carol is the greatest number because she slept "longer."

Here's a different problem:

Justin lives 5 miles from school. Cady lives 8 miles from school. How much farther from school does Cady live than Justin?

The first and second sentences do not tell us who the greatest number is. The third sentence does, because it says that Cady lives "farther" from school than Justin.

You have to read the problems carefully to determine the three parts of the number family.

Here are more word problems like the ones we've already learned.

You have some seashells. At the beach you collect 30 more. You end up with a collection of 45 seashells.

You h­ave 90 crayons. You lose some crayons. You end up with only 75 crayons.

The first problem is telling you the greatest number and asking you to find how many seashells you first had.

In the second problem, the values go backward from the greatest number. Put a box between your values to represent the word some, like this:

Remember, it is very important to read the problems carefully so you know how to solve them.

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