# MATH EXPONENTIAL HELP?

The grass on a golf course needs to be cut when it reaches a height of 3 cm. If the height of the grass is 15 mm on Sunday and it grows at a rate of 3 mm per day, when is the next day it should be cut?

2. How many terms are there in the sequence: 10, -6, 18/5, -54/25, .... -4374/15625 ?

### 1 Answer

- sepiaLv 73 months ago
1).

The grass on a golf course needs to be cut when it reaches a height of 3 cm.

If the height of the grass is 15 mm on Sunday and it grows at a rate of 3 mm per day, when is the next day it should be cut?

In 5 days its growth equals 15 mm.

5 days after Sunday is Friday.

Hence it should be cut on Friday.

2).

How many terms are there in the sequence:

10, -6, 18/5, -54/25, .... -4374/15625

-4374/15625 = -2 (-1)^n 3^(n - 1) 5^(2 - n)

Integer solution:

n = 8

There are 8 terms in the sequence.