Free Throw Probability

What's the probability of someone making a certain amount of free throws in a row given their free throw success percentage? If Sally makes 50% of her free shot throws, then Sally's probability of making 5 in a row would be 3%.

Examples

free_throws("75%", 5) ➞ "24%"

free_throws("25%", 3) ➞ "2%"

free_throws("90%", 30) ➞ "4%"

Notes

• The success rate is a string.
• The function should return a string with the percent sign.
• Round your answer to the nearest whole number.