Question

Given the sequence 10, 20, 40, 80,.... find 25th term​

Answer 1

167,772,160

Explanation:

-Each term is multiplied by 2-

10, 20, 40, 80, 160, 320, 640, 1,280, 2,560, 5,120, 10,240, 20,480, 40,960, 81,920, 163,840, 327,680, 655,360, 1,310,720, 2,621,440, 5,242,880, 10,485,760, 20,971,520, 41,943,040, 83,886,080, 167,772,160

167,772,160 is the 25th term

Answer 2

This sequence is a geometric sequence so u want to find out the formula

The formula for a geometric sequence is: ar to the power of n-1

A= first term and r= the factor between the terms (called the common ratio)

Now we juss input it in the formula

10 x 2 to the power of n-1

Now we want to work out the 25th term so n=25 we do 25-1=24

So it’s 10*2 to the power of 24

Answer: 167772160

Hope this helped