Step by step
The question
Question: 24 of 64 fans buy a shirt.
About how many of 4,000 buy a shirt?
1 The fraction in the sample
24 out of 64: that is 24/64.
2464
The 64 fans are a sample: a small group that stands for everyone.
sample: 64 fans
24 and 64 can both be divided by 8.
So it is 3/8.
= 24 ÷ 864 ÷ 8 = 38
2 Use it for everyone
We expect the same fraction of all 4,000: 3/8 of 4,000.
Of means times.
= 38 × 4,000
4,000 divided by 8 is 500.
Then times 3.
= 3 × 500
4,000 ÷ 8 = 500
That is about 1,500.
= ≈ 1,500
Careful!
A sample only shows about how many.
So the answer is a good guess, not an exact count.
Careful: about, not exactly
So about 1,500 fans buy a shirt.
3 Check
Let's check: 1,500 out of 4,000.
Divide the top and the bottom by 500: 3/8, the same fraction as the sample.
So the answer is right!
1,5004,000 = 1,500 ÷ 5004,000 ÷ 500 = 38
Let's look back.
First: the fraction in the sample.
Then: use it for everyone.
Last: check.
Answer
Careful: about, not exactly