1 three fourths -- seven tenths

Find the missing number. a. 3 : 24 = : 72 b. : 18 = 5 : 9 c. 6: = 36 : 36

Determine the relationship of ab and cd given the following points

Proceed as in example 3 in section 6.1 to rewrite the given expression using a single power series whose general term involves xk. ∞ n(n − 1)cnxn − 2 n = 2 − 4 ∞ ncnxn n = 1 + ∞ cnxn n = 0