If c < d and x > 1, which of the following must be true

Which geometric principle is used to justify the construction below?

From a group of 10 men and 8 women, 5 people are to be selected for a committee so that at least 4 men are on the committee. howmany ways can it be done?

Ashop has a sale that offers 20% off all prices. on the final day they reduce all the sale prices by 25% linz buys a ratio on the day. work out the overall percentage reduction on the price of the ratio