Question Number 55583 by Tinkutara last updated on 27/Feb/19
Answered by mr W last updated on 27/Feb/19
$$\frac{\mathrm{2}×\mathrm{2}!\mathrm{2}!}{\mathrm{4}!}=\frac{\mathrm{1}}{\mathrm{3}} \\ $$$$\Rightarrow\left({a}\right) \\ $$
Commented by mr W last updated on 27/Feb/19
$$\left.{you}\:{are}\:{right}\:{sir}.\:{answer}\:{a}\right)\:{is}\:{correct}. \\ $$
Commented by Tinkutara last updated on 27/Feb/19
Thanks Sir!
Commented by Tinkutara last updated on 27/Feb/19
Sir can you explain please?
Why answer is not a because there may also be a case when two good machines are detected in first two trials?