Question

A camera attached to a telescope photographs a star’s image once every 0.045 seconds. How many complete images can the camera capture in 3 seconds?

Answer 1

Answer: 66

Explanation:

Given : A camera attached to a telescope photographs a star’s image once every 0.045 seconds.

i.e. the number of complete images can the camera capture in 0.045 seconds = 1

Then , the number of complete images can the camera capture in 1 second =
`(1)/(0.045)`

The number of complete images can the camera capture in 3 seconds will be

`(1)/(0.045)*3=66.6666666667\approx66`

Hence, the number of complete images can the camera capture in 3 seconds = 66

Answer 2

One image can capture within 0.045 seconds and we consider this as a rate as 0.045 seconds per image or maybe 200/9 images per second.

It is much convenient to say for the rate always is controlled by the time, and the unit of our choice is image per second. The formula of our rate is expressed as
r = i/t
where r = rate, i = number of captured images, t = time

For 3 seconds, the images has about
i = rt = (200/9)(3) = 66.67