Question 1122260
2C1*8C2/10C3 is probability of one defective item, and that is 2*28/120=56/120
or
(2/10)(8/9)(7/8)+(8/10)(7/9)(2/8)+(8/10)(2/9)(7/8)=336/720=56/120

For 2 defective items
3C2*7C0/10C3=3/120 
The probability of rejection is 59/120=0.492