Least and Most( Week 16 Practice) 1. There are 40 balls of 4 different colors in a bag. There are an equal number of balls for each color. At least how many balls need to be taken out from the bag so that there are 3 balls which are the same color? 2. If humans have up to 120,000 hairs, at least how many people will have same number (including zero) of hair(s) with someone else in a city with a population of 170,000 people? 5. A bag contains 222 beads. All the beads are the same, but in 6 different colors. There are equal number of beads for each color. If Mary is blindfolded and picks beads from the bag, what is the fewest number of beads she has to pick in order to be absolutely sure that there are 7 beads of the same color? |