What is the value of the fourth term in a geometric sequence for which a1 = 30 and r = 12?

To find the fourth term in a geometric sequence, we can use the formula for the nth term of a geometric sequence, which is given by:

an = a1 * r(n-1)

Here:

  • a1 is the first term of the sequence,
  • r is the common ratio,
  • n is the term number.

In this case, we know

  • a1 = 30,
  • r = 12,
  • and we want to find a4 (the fourth term).

Plugging these values into the formula:

a4 = 30 * 12(4-1)

Calculating further:

a4 = 30 * 123

Now calculating 123:

123 = 12 * 12 * 12 = 1728

So, substituting back, we have:

a4 = 30 * 1728

Now we can do the multiplication:

a4 = 51840

Therefore, the value of the fourth term in the geometric sequence is 51840.

More Related Questions