Evaluating the given sequence, it is evident that the next number is twice the number prior to it. Thus, the given is a geometric sequence with first term (a1) equal to 1 and common ratio of 2. The geometric series may be calculated by the equation,
Sn = a1 x (1 - r^n) / (1 - r)
where Sn is the sum of n terms in this case, n = 11. Substituting the known values,
<span> Sn = 1 x (1 - 2^11) / (1 - 2) = 2047 </span> Thus, S11 is 2047.
Step-by-step explanation: The total number of pizzas is 12 + 18 = 30. Mitchel bought 12 of those 30 pizzas. To find the percentage you do the portion/total. Thus 12/30 = 0.4, as a proportion. To turn a proportion into a percentage simply multiply by 100. 0.4 * 100 = 40%
