A coin is tossed 400 times and head appears 240 times. Test at 5% level of singificance about the unabiasedness of the coin.

A coin is tossed 900 times and head turns up 480 times. Test the hypothesis that the coin is unbiased.(Level of significance = 5%)

A fair coin is tossed 10 times. Find the probability of getting exactly five heads.

(i) A coin is tossed. What is the type of the event ‘Head or tail appears on the coin’?

Three coins are tossed together. Write down all the probable outcomes of the trial.Also find the probabilities of the events of getting(iii)at least 2 Heads

Three coins are tossed together. Write down all the probable outcomes of the trial.Also find the probabilities of the events of getting (i)3-Heads

Three coins are tossed together. Write down all the probable outcomes of the trial.Also find the probabilities of the events of getting(ii)2 Heads

Identify all the probable simple events obtained from the trial of tossing a coin two times and find their probabilities. Also describe one impossible event and one sure event associated with the above trial.

A brass rod of length 50 cm and diameter 3.0 mm is joined to a steel rod of the same length and diameter. What is the change in length of the combined rod at 250 ^@C , if the original lengths are at 40.0 ^@C ? Is there a ‘thermal stress’ developed at the junction? The ends of the rod are free to expand (Co-efficient of linear expansion of brass = 2.0 xx 10^-5K^-1 steel = 1.2 xx 10^-5 K^-1) .

Two coins are tossed simultaneously. Find the probability of getting exactly one head.