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A single postage stamp costs $0.44.
How much would a roll of 1,000 stamps cost?
So we're going to have 1,000 stamps, and each of them costs
$0.44, so we can multiply the 1,000 stamps
times $0.44 per stamp.
And then we just have to multiply the two numbers.
Now when you first multiply decimals, you can just pretend
like they're whole numbers, and then worry about the
decimals later.
So we can view this as 1,000 times 44, and then worry about
the decimals.
What's 1,000 times 44?
You could work it out.
You could say, OK, 4 times 0 is 0.
4 times 0 is 0.
4 times 0 is 0.
4 times 1 is 4.
You get 4,000 here, And you put a zero here, and you
multiply that, you get 40,000.
You'd add it all up.
But I think we know from experience, dealing with
multiplying by powers of ten, or by multiples of ten, that
really, 44 times 1,000 is just 44,000, so we can just write
it out here.
So 44 times 1,000 is 44,000.
Let me not put a comma there just yet.
That's 44 times 1,000.
Now this isn't 44.
This is 0.44.
So in both numbers that we're multiplying, we have exactly
one, two numbers to the right of the decimal.
So our answer, our product, has to have two numbers to the
right of the decimal.
So we count from the right.
We count one, two.
Stick the decimal right there.
So our answer is 440.00, and these trailing zeroes really
add nothing there.
So 1,000 times 0.44, or forty-four
cents really, is 440.
Or it's going to cost us $440 to buy 1,000 stamps, which
makes sense.
Because 0.44, think about it.
It's a little bit less than half.
0.5 would be half.
So this is a little bit less than half of $1,000.
A half would be $500.
This is a little bit less.