The record of a weather station shows that out of the past 250 consecutive days, its weather forecasts were correct 175 times. (i) What is the probability that on a given day it was correct? (ii) What is the probability that it was not correct on a given day?

According to a meteorological report for 300 consecutive days in a year , its weather forecasts were correct 180 times . Out of these days , one day is chosen at random . What is the probability that the weather forecast was not correct on that day ?

In a hospital, there are 5 dialysis machine. The chance of any one of them being defective during a day is 1/10 . Find the probability that two machines will be out of order on the same day. What is the probability that at least one machine is in working order? Is this situation alright for a small hospital?

Two customers Shyam and Ekta are visiting a particular shop in the same week (Tuesday to Saturday). Each is equally likely to visit the shop on any day as on another day. What is the probability that both will visit the shop on : consecutive days ?

In answering a question in a multiple choice test a student either knows the answer or guesses. Let 3/4 be the probability that he knows the answer and 1/4 be the probability that he guesses. Assuming that a student who guesses at the answer will be correct with probability 1/4 . What is the probability that a student knows the answer, given that he answered it correctly ?

A factory has two machines A and B. Past record shows that machine A produced 60% of the items of output and machine B produced 40% of the items. Further, 2% of the items produced by machine A and 1% produced by machine B were defective. All the items are put into one stockpile and then one item is chosen at random from this and is found to be defective. What is the probability that it was produced by machine B?

Two customers Shyam and Ekta are visiting a particular shop in the same week (Tuesday to Saturday). Each is equally likely to visit the shop on any day as one another day. What is the probability that both will visit the shop on (i) the same day ? (ii) consecutive days ? (iii) different days ?

Two dice are thrown simultaneously 500 times. Each time the sum of two numbers appearing on their tops is noted and recorded as given in the following table: If the dice are thrown once more, what is the probability of getting a sum: 3