There are 9 counters. 4 red. 2 blue. 3 yellow. 2 counters are picked at random. what is the probability that at least 1 yellow counter is picked?

Aprisoner is trapped in a cell containing three doors. the first door leads to a tunnel that returns him to his cell after two days of travel. the second leads to a tunnel that returns him to his cell after three days of travel. the third door leads immediately to freedom. (a) assuming that the prisoner will always select doors 1, 2 and 3 with probabili- ties 0.5,0.3,0.2 (respectively), what is the expected number of days until he reaches freedom? (b) assuming that the prisoner is always equally likely to choose among those doors that he has not used, what is the expected number of days until he reaches freedom? (in this version, if the prisoner initially tries door 1, for example, then when he returns to the cell, he will now select only from doors 2 and 3.) (c) for parts (a) and (b), find the variance of the number of days until the prisoner reaches freedom. hint for part (b): define ni to be the number of additional days the prisoner spends after initially choosing door i and returning to his cell.

The trapezoid is composed of a rectangle and two triangles. what is the area of the rectangle? what is the total area of the triangles? what is the area of the trapezoid? a) 48 cm2; 32 cm2; 80 cm 2 b) 48 cm2; 16 cm2; 64 cm 2 c) 128 cm2; 32 cm2; 160 cm 2 d) 128 cm2; 16 cm2; 144 cm 2

Grading scale 1 has the following weights- (tests- 50% quiz- 25% homework- 15% final exam- 10%). calculate your final average if your performance in the class is as follows-test grades- {88, 84, 90, 75, 70, 81); quiz grades- {88, 67, 90, 90, 45, 99, 76, 98, 100}; homework- 90; final exam- 75