Let Y 1 , Y 2 , . . . , Y n be a random sample

Question:

Let Y₁, Y₂, . . . , Y_n be a random sample from a normal distribution where the mean is 2 and the variance is 4. How large must n be in order that

P(1.9 ≤ Y̅≤ 2.1) ≥ 0.99

Distribution
The word "distribution" has several meanings in the financial world, most of them pertaining to the payment of assets from a fund, account, or individual security to an investor or beneficiary. Retirement account distributions are among the most...