Us the sum and sequence features of a graphing calculator to

Us the sum and sequence features of a graphing calculator to eval the following sum. Round to the nearest thousandth.

Solution

the given expression sigma ( j=2 to 7) 3 (0.6)^j

= 3 (0.6)^2 + 3(0.6)^3 +3(0.6)^4 +3(0.6)^5 +3(0.6)^6 +3(0.6)&7

=3(0.36) +3(0.216) +3(0.1296) +3(0.07776) +3(0.047)+3(0.028)

=1.08 +0.65 +0.39 +0.234+0.141+0.084

=2.579

=3( rounding)