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Question
80 bulbs are selected at random from a lot and their life time (in hrs) is recorded in the form of a frequency table given below:
| Life time (in hours) | 300 | 500 | 700 | 900 | 1100 |
| Frequency | 10 | 12 | 23 | 25 | 10 |
One bulb is selected at random from the lot. The probability that its life is 1150 hours, is
Options
`1/80`
`7/16`
0
1
Solution
0
Explanation:
Total bulb in a lot, n(S) = 80
Number of bulbs whose life time is 1150, n(E) = 0
Probability that its life time is 1150 h = `(n(E))/(n(S)) = 0/80 = 0`
Hence, the probability that its life time is 1150 is 0.
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