Question

Write the next explicit form of this sequence, given a1 = 20 and r = 0.5 (12), and find n = 15.

A) 9

B) 10

C) 11

D) 12

Answer 1

B) 10. The next explicit form of the sequence is 10.

Step-by-step explanation:

The explicit form of a geometric sequence is given by the formula: an = a1 * r(n-1), where an is the nth term, a1 is the first term, and r is the common ratio. In this case, we have a1 = 20 and r = 0.5. To find the 15th term, we can substitute these values into the formula and solve for a15:

a15 = 20 * (0.5)(15-1) = 20 * 0.514

a15 = 10