Victor measured a circular lid and found d, the diameter, was 8 inches and c, the circumference was 25 inches.

And we also know that circumference C =25 inches and the formula for this circumference is given by:

We want to find the value of and solving from the last equation we got:

And replacing we got:

So then the approximation for the value of and that's very close to the real value of
Step-by-step explanation:
For this case we know that the diameter d =8 in. And we can find the radius from this info since d = 2r with r representing the radius. If we solve for r we got:

And we also know that circumference C =25 inches and the formula for this circumference is given by:

We want to find the value of and solving from the last equation we got:

And replacing we got:

So then the approximation for the value of and that's very close to the real value of

22.