A sled needs to be pulled by a team of 4 huskies, chosen from a group of 10 available huskies. How many different 4-dog teams of huskies can be selected to pull the sled?  165  210  220  5,040

In a competition of 50 professional ballroom dancers, 22 compete in the fox-trot competition, 18 compete in the tango competition. and 6compete in both the fox-trot and tango competitions. How many dancers compete in the foxtrot or tango competitions?

A commuter must travel from Ajax to Barrie and back every day. Four roads join the two cities. The commuter likes to vary the trip as much as posible, so she alwaysleaves and returns by different roads. In how many different ways can she make the round-trip?

Engine pistons and cylinder heads are made of an aluminum casting alloy that contains 4% silicon, 1.5% magnesium, and 2% nickel. Round the answers to the nearest tenth kilogram. a. How many kilograms of silicon are needed to produce 575 kilograms of alloy? b. How many kilograms of magnesium are needed to produce 575 kilograms of alloy? c. How many kilograms of nickel are needed to produce 575 kilograms of alloy?