The circular face of a watch has an area that measures between 800 and 900 square millimeters.

what could be the radius of the watch face? use 3.14 for pi.

14 mm
15 mm
16 mm
17 mm

Third option.

Step-by-step explanation:

The area of a circle can be calculated with the following formula:

Where "r" is the radius of the circle.

Using , this is:

According to the information given in the exercise, the area of the circular face of the watch measures between 800 and 900 square millimeters. Knowing this, we can check each option:

1) Substitute into the formula and evaluate. Then:

 (This could not be  the radius of the watch face)

2) Substitute into the formula and evaluate. Then:

 (This could not be  the radius of the watch face)

3) Substitute into the formula and evaluate. Then:

 (This could be  the radius of the watch face)

4) Substitute into the formula and evaluate. Then:

 (This could not be  the radius of the watch face)

the final amount you will pay is $68.04.

the tip is determined by the pre-tax amount, so we calculate the tip based on the original bill, not after we've added sales tax.

to find the tip:

we can divide 54.00 by 100 to get 1% of 54. then we multiply that by 18.

54 / 100 = .54

.54 x 18 = 9.72

tip = 9.72$

to find the tax:

we can divide 54.00 by 100 to get 1% of 54. then we can multiply that by 8 to get 8%.

54 / 100 = .54

.54 x 8 = 4.32

tax= 4.32

now we can add the tip and tax to the bill to get our total.

54 + 9.72 + 4.32 = 68.04

total: $68.04

step-by-step explanation: