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Do you first
panic
when you're asked to solve a word problem? You probably go
through the steps you learned.
- Read the problem. Decide
what is wanted.
- Plan your strategy.
- Solve. Do the arithmetic.
- Look back. check
your work.
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But many times, there is just
too much information given!!! |
So, this lesson is going to give you
practice as to what is
important and what is not!
What is important is also
known as
relevant information.
What is not important is
also know as
irrelevant. In this lesson you
will learn how to decide what is relevant and what is
irrelevant.
And let's face it, in real life, we often have to decide which
information we need to solve a problem and which information we do not
need.
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relevant |
irrelevant |
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important information |
not
important information |
|
need this to solve
problem |
not needed to
solve problem |
Let's look at some examples you could find
in a book.
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From Syracuse, a train, a car,
and a plane left for New York City at noon. It will take
the train 5½ hours to get there. The car can
travel 55 mph. What time will the train get to New York City? |
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When you look at the question, it only asks for the train time.
It does not care about the car's speed. Therefore the
relevant
information is: From Syracuse,
a train,
a car, and a
plane
left for New York City
at noon. It will take the train 5½ hours to get there. |
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A man can go 400
miles on a full tank of gas. He needs to go 100 miles
today and has a half tank of gas. He has $100 in his
wallet. Does he need to buy more gas before he goes? |
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When you look at the question, it only asks if a half tank can
get him 100 miles. It does not care about the money he has
in his wallet. Therefore the
relevant
information is: A man
can go 400 miles on a full tank of gas. He needs to go 100
miles today and has a half tank of gas.
He has $100 in his wallet. |
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In order for the
kite to fly properly, the wind needs to be at least 15 mph.
The kite cost $5.98. The wind speed today is 28 mph.
Can I fly a kite today? |
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When you look at the question, it only asks if I can fly a kite
today. It does not care about the cost of the kite.
Therefore the
relevant
information is:
In
order for the kite to fly properly, the wind needs to be at
least 15 mph.
The kite cost $5.98.
The wind speed today is 28
mph.
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OK, ready for one more
before you practice?
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I only have $5.00 to
spend today at the sale. I want to buy a tablet that costs
$1.95 and a special pencil that costs $2.48. I earned $8
last week raking leaves. Do I have enough money to buy my
two items? |
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When you look at the question, it only asks if you have enough
money to buy two items. It does not care about the money earned last week. It cares only about the money I have
TODAY. Therefore the
relevant
information
is:
I only have $5.00 to
spend today
at the
sale.
I
want to buy a tablet that costs $1.95 and a special pencil that
costs $2.48.
I
earned $8 last week raking leaves. |
Ready to practice?
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