Arithmetic sequence
Arithmetic Series
Geometric Sequence
Geometric Series
100

Determine  whether this formula is explicit or recursive:   a1=-4, an=2an-1

Recursive

100

What is the formula to find the sum of a finite arithmetic series?

(a1+an)/2 . n

100

What is the recursive formula to find the nth term of a geometric sequence?

a(n-1).(r)

100

The common ratio in a geometric series is 6 and the first term is 240. Find the sum of the first 7 terms in the series.

13436880

200

What is the explicit formula to find the nth term of an arithmetic sequence?

an= a1+d(n-1)

200

Find the sum of: 2,4,6,8,10,12,14,16,18,20.

110

200

d(n)=4(-5)(n-1)

What is the sixth term in the sequence?

-12500

200

Find the sum of the first 9 terms in the following geometric series . Round your answer to the nearest hundreth.

63+21+7+....

94.50

300

What is the next term of this arithmetic sequence?

-3,-8,-13,-18,_____

-23

300


13275

300

b(1)=20

b(n)=b(n-1).(2)

What is the 5th term in the sequence?

240

300

The common ratio of a geometric series is 1/4 and the sum of the first four terms is 170. Find the first term of the series.

128

400

b(n)=-2-4(n-1), find the 12th term.

-46

400

The arithmetic series ais defined by the formula:

a1=6

ai=a(i-1)-4

Find the sum of the first 255 terms of this sequence.

-128520

400

d(n)=7/16.(2)(n-1)

What is the fourth term of the sequence?

7/2

400

The common ratio of a geometric series is 4 and the first term of the series is 22. Find the sum of the first 8 terms of the series.

480,590

500

d(1)=4

d(n)=d(n-1)-16

Find the 4th term in the sequence.

-44

500

Find the sum of -60-54-48+...+2028+2034.

345,450

500

Find the missing term for this geometric sequence: 

4,___,5.76.

4.8

500

Each year, Sarah earns a salary that is 5% higher than her previous year's salary. In her first four years at this job, she earned a total of ₱ 1,000,000. What was Sarah's salary in her 1st year at this job? Round to the nearest hundredth.

₱ 232,011.83