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2 hats and 4 scarves, how many outfits

Step by step, with the reason for every step · Counting choices · Probability

Step by step

The question

Question: There are 2 hats and 4 scarves.

How many outfits can be made with one of each?

1 Count the choices

2 Draw a tree

3 Multiply

Each of the 2 hats goes with 4 scarves.

So we multiply: 2 × 4.

outfits = 2 × 4

This is the counting principle: multiply the number of choices.

counting principle:
multiply the choices

2 groups of 4: that is 2 times 4.

4 + 4 = 2 × 4

Careful!

We do not add the choices.

Every choice goes with every other one, so we multiply.

Careful: not 2 + 4 = 6 ✗

2 times 4 is 8.

2 × 4 = 8

So there are 8 outfits.

outfits = 8

4 Check

Let's check: we count the ends of the tree.

There are 8 ends, one for each.

So the answer is right!

8 ends = 8 outfits

Let's look back.

First: count the choices.

Then: draw a tree.

Then: multiply.

Last: check.

Answer
outfits = 8

Your turn

Try this one yourself, then check:

Show the answer
outfits = 6

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