Section 1.1 Homework Hints
Problems 14-17
See Examples 1 and 2; use Pascal's triangle. Draw the figure you are
working with, and then either label the number of ways to get to each
vertex (as in Example 1), or else count the number of rows and columns
from A to B. For example, in Problem 15, from A go up two rows and then
over three rows. Start at the top of Pascal's triangle, and count down
two and then over three to find the entry, which is the correct answer.