Use Mathematical Induction to prove the following: n
1.1 ∑ [ + 2]/[( + 1)(2^r)] = 1 - [1]/[(n + 1)(2^n)] for all ∈ ℕ
r=1

Scores on the cognitive scale of the bayley-scales of infant and toddler development range from 1 to 19, with a standard deviation of 3. calculate the margin of error in estimating the true mean cognitive scale score, with 99% confidence, if there are 12 infants and toddlers in a sample.