How many groups of 20 would you need to make 200?

Write an explicit formula that represents the sequence defined by the following recursive formula:

For each proportion find the unknown number x 1/5/8=×/15

Awoman has 14 different shirts: 10 white shirts and 4 red shirts. if she randomly chooses 2 shirts to take with her on vacation, then what is the probability that she will choose two white shirts? show your answer in fraction and percent, round to the nearest whole percent.