A bowl contains 10 chips, of which 8 are marked $2 each and 2 are marked $5 each. Let a person choose, at random and without replacement, three chips from this bowl. If the person is to receive the sum of the resulting amounts, find his expectation.

Answer:$7.8Step-by-step explanation:We have three cases to this question which are; (a). Getting two $2 and one $5 (b). Getting one $2 and two $5(c). Getting all three $2Note: there are 10:3 ways of doing this.Computing the probability of each, we have: (a). We have {8;2} {2;1} ways to get two $2. Therefore, the probability gives; (8;2) (2;1)÷ 10;3) we get 9 here. (b). (8;1)(2;2)÷ (10;3)We have 12 here. (c). (8;3)(2;0)÷ (10;3)= 6 The expectation; (10;3)= 120, (8;3)(2;0)= 56.(8;2)(2;1)= 56 and (8;1)(2;2)= 8.So, the expectation is; 9.56+12.8+6.56÷120= 936÷120= 39÷5= $7.8.