A grocer stacks oranges in a four-sided pyramid that is 7 layers high. How many oranges are in the pile? The explicit formula for a pyramidal sequence is P(n)= n(n+1)(2n+1) 6 A.120 B.504 C.840 D.140
Short Answer D P(1) = 1(1+1)(2*1 + 1)/6 P(1) = 1(2)(2 +1) / 6 P(1) = 1(2)(3)/6 P(1) = 1
P(2) = 2(2+1)(2*2 + 1) / 6 P(2) = 2(3)(5) / 6 P(2) = 5 So this formula is adding as it goes along. To Find the Total all we need do is use the formula to calculate P(1) to P(7)
