1. You are given the following formula for the probability of a 20-year-old surviving at least n more years:

_n p₂₀ = 0.80 0.01n.

What is the probability (40) will survive to at least age 65?

• A. 35.0%
• B. 58.3%
• C. 55.0%
• D. 63.6%

2. Let E_1, E₂, E₃ and E₄ be events with the following probabilities: P(E₁) = 1/4, P(E₂) = 2/5, P(E₃) = 1/6, P(E₄) = 1/5.

E₁ and E₂ are mutually exclusive events, while E₃ and E₄ are independent events.

Let,

A = probability of neither E₁ nor E₂ occurring

B = probability of exactly one of E₃ or E₄ occurring.

What are the values of A and B?

• A. A = 0.35, B = 0.300
• B. A = 0.15, B = 0.148
• C. A = 0.10, B = 0.300
• D. A = 0.35, B = 0.150