Answer:
16.
Step-by-step explanation:
since given the radius and the formula of the circumference of a circle is 2pie*r
So just add all of them together and you get 405. Then divide by the amount of numbers there is which is 5. So 405 divided by 5. The answer is 81.
Change the mixed numbers into improper fractions:
5/3 X 9/2
Reduce - the 3 and 9 can be simplified
5/1 X 3/2
multiple numerators and denominators
15/2
Not sure how you need the answer - i would change it into a mixed number
7 1/2
So... 4 folks, working for 8hours per day, do it in 15days
hmm alrite...so 4 folks working for 8hrs in 1 day, each one does 8, 4 of them, 4*8 = 32, so, they do 32 workhours every day, now for 15 days, that'd be 32*15, or 480
so, the whole job really takes 480 hours
now hmm let's see, the firm decides to increase the folks, but decrease the hours, so, 5 folks each working 6hours every day
how many workhours total? well 5*6 = 30
each is working 6hrs, 5 of them, so 30 workhours
how long will it take them if they only do 30 workhours everyday?
well the whole job is 480hours