A sporting goods store estmates that 20% of the students at a nearby university ski downhill and 15% ski cross country. Of those who ski downhill, 40% also ski cross country. What percentage of these students ski both down hill and cross country? Write as a decimal.
Down-hill =20%
Cross-country =15%
In down-hill and cross-country (20%)(40%) = 0.08
To find the percentage of students who ski both downhill and cross country, we can use the concept of conditional probability.
First, let's calculate the number of students who ski downhill and cross country. We start with the overall percentage of students who ski downhill, which is 20%. Then, we find the percentage of students who ski cross country given that they also ski downhill, which is 40% of the 20%.
Percentage of students who ski both downhill and cross country = 20% * 40% = 0.20 * 0.40 = 0.08
So, 8% of the students ski both downhill and cross country.
Therefore, the percentage is 8% expressed as a decimal, which is 0.08.