JEE Main202131 Aug 2021Morning ShiftMathematicsProbabilityActual
An electric instrument consists of two units. Each unit must function independently for the instrument to operate. The probability that the first unit functions is 0 . 9 and that of the second unit is 0 . 8 . The instrument is switched on and it fails to operate. If the probability that only the first unit failed and second unit is functioning is p , then 98 p is equal to
Correct answer
0
Step-by-step solution
Given that An electric instrument consists of two units. Each unit must function independently for the instrument to operate. The probability that the first unit functions is 0 . 9 and that of the second unit is 0 . 8 . The instrument is switched on and it fails to operate. If the probability that only the first unit failed and second unit is functioning is p . Let E 1 = Event of first unit is working E 2 = Event of second unit is working P E 1 = 0 . 9    P E 2 = 0 . 8 We know that P E   =   1 &