The sum of the first 6 terms of a geometric series is
15, 624 and the common ratio is 5
what is the first term of the series?

4

Step-by-step explanation:

The sum to n terms of a geometric sequence is

=

where a is the first term and r the common ratio

Here r = 5 and a has to be found, thus

= , so

= 15624

Multiply both sides by 4

15624a = 62496 ( divide both sides by 15624

a = 4

  b.   the average rate of change of f(x) is less than the average rate of change of g(x).

step-by-step explanation:

since the length of the interval is the same in each case, we only need to compare the change in y-value to see which is greater.

so the change in y-value for function f is (6 )) = 9.

the table tells us

so the change in y-value for function g is (31 -1) = 30.

the change in y-value of f(x) on the interval is less than the change in y-value of g(x) on the same interval, so the average rate of change of f(x) is less than the average rate of change of g(x).

d

step-by-step explanation: