How to spot this family

• Prawns, CLT on a sum：Given individual μ, σ, you take n of them, and are asked for "the probability that eating all of them (= the total) exceeds some upper limit" · b) the reverse: "what upper limit is exceeded by only 5%"
• Lift max load, CLT on a sum：Given people's weight μ, σ, with n people entering a lift; asks the probability of exceeding the maximum load · b) reverse question "to guarantee only 0.5% overload, what should the maximum load be set to"
• Daily yield, CLT on a mean："average yield for a 31-day month falls below 20.2" · b) reverse question "trigger an investigation in only 4% of months, what should the lower limit be set to"
• Bolts, two-sided spec + solve for n："average weight of the batch is between a and b" (two-sided!) · a) asks for the proportion not meeting spec · b) solve back for n
• Tree heights, CLT + solve for n："ready for logging if a sample of trees has a mean height exceeding 27 m" · b) "How many trees should have been sampled" → solve back for n!