Q:

dose any one know these 4 answer i am raly struggling and i need the help asap

Accepted Solution

A:
I can help.

Remember that the equation for circumference is 2(pi)(r). For the first question, we are given the circumference, 235.5 cm. So, we can reverse this equation to find the radius, so 235.5=2(pi)(r). We divide 235.5 by 2 to get 117.25, and then divide it by pi to get approximately 37.5 cm. Now we multiply by 2 to find the diameter since d=2r, and the diameter is about 75 cm, or D.

We can do the same thing for the second question, so 141.3=2(pi)(r), or 70.65=(pi)(r). Dividing this by pi results in r=22.5 ft, D. again.

Now we can do the same for the third question, and make the equation 47.1=2(pi)(r), or 23.55=(pi)(r). Now divide by pi and get r=7.5. Multiplying this by 2 for diameter yields 15 in, or B.

For the last problem, you do 157=2(pi)(r), or 78.5=(pi)(r). Dividing 78.5/pi=25. So, r=25 m, or A.

Hope this helps!