Q1: The probability that the load on a scaffolding will exceed the design load of 3 tonnes is 0.15. At the same time, the probability that the strength of the scaffolding will be more than 3 tonnes is 0.85. The probability that the scaffolding will fail is

ANS:C - 0.0225

Scaff will fail if load on scaff will be more than 3 tonne or strength of scaff is less than 3t.

P(S<3t)=i.e probability that strength of scaff will be less than 3 tonne= 1-0.85= 0.15.

P(L>3t)= 0.15, load on scaff is more than 3t.

So probability of failure= P(s<3t)x P(L>3t)
P= 0.15x 0.15= 0.0225.