Posted by **Speedo** on Saturday, September 7, 2013 at 3:02pm.

The 23rd term in a certain geometric sequence is 16 and the 28th term in the sequence is 24. What is the 43rd term?

It is not 48.

- mAtH -
**Steve**, Saturday, September 7, 2013 at 4:11pm
a+22d = 16

a+27d = 24

a = -96/5

d = 8/5

-96/5 + 42*8/5 = -96/5 + 336/5 = 240/5 = 48

If 48 is marked wrong, the key is in error. You could have checked it yourself.

- mAtH -
**Speedo**, Saturday, September 7, 2013 at 4:33pm
This is what you did wrong, i think. YOu multiply not add.

- mAtH -
**Steve**, Saturday, September 7, 2013 at 4:47pm
Or, look at it this way. From T23 to T28 is 5 terms, and the value grew by 8.

From T28 to T43 is 15 terms = 3*5, so the value will grow by 3*8, or 24.

24+24 = 48

## Answer this Question

## Related Questions

- MaTh - The 23rd term in a certain geometric sequence is 16 and the 28th term in ...
- MaTh - The 23rd term in a certain geometric sequence is 16 and the 28th term in ...
- Math - A sequence is formed by adding together the corresponding terms of a ...
- Math - 1. What is the tenth term of the geometric sequence whose first term (a1...
- Math - 3,5,-5... The first term in the sequence of #'s shown above is 3. Each ...
- MaTh - A certain 300-term geometric sequence has first term 1337 and common ...
- Maths - 1..The first 2 terms of a geometric progression are the same as the ...
- math Question - the 5th term in a geometric sequence is 160. The 7th term is 40...
- math - in a certain geometric sequence, the third term is 8 and the sixth term ...
- math - in a certain geometric sequence, the third term is 8 and the sixth term ...