Question

4 coins were tossed 160 times and the following results
were obtained


No. of heads:0 1 2 3 4
observed frequency : 17 52 54 31 6​

Answer 1

Answer:

Four coins are tossed 160 times and 0, 1, 2, 3, 4 heads appeared, respectively 19, 54, 58, 23 and 6 times. That is, observed frequencies are 19, 54, 58, 23, 6 and N=160

Test whether the coins are balanced and randomly selected or not.

Null hypothesis,The coins are balanced.

Alternative hypothesis, The coins are not balanced.

Let the level of significance be,

Number of categories,

Compute the degrees of freedom.

At with , the critical value from the chi-square table,

Decision Rule: Reject if