Problem set#1: sigma, algebra review, data types and measures of central tendency: suppose that x1 = 8, x2 = 9, x3 = 3, x4 = 6. Find: (a) (cid:2) (b) (cid:2)(cid:3) (c) (cid:4) (cid:2)(cid:5)(cid:3) (d) 1,000(cid:2: the following table lists six values of x, w and z x 7 11 8. 4 w 5 15 7 10 z 2. Compute the value of (a) (cid:2)(cid:9) (b) (cid:4) (cid:2)(cid:5)(cid:4) (cid:9)(cid:5) (c) Note: = is the lowercase greek letter mu and = is the lowercase greek letter sigma . Weighted mean questions: a person makes 3 investments and earns 7%, 8% and 9%. The average rate of return earned is (7+8+9)/3 = 8% only if: a person invests ,000 at 7% for one year, ,000 at 8% and ,000 at 9%. What average rate of return was earned on the three investments: your parents have assembled the following investment portfolio and estimated the following rates of return: