C= 2*pi*r pi= approx. 3.14 So The first one with the radius being 18 would be approximately 113.04 BECAUSE 18 * 2 = 36 36*3.14= 113.04 DO THE SAME PROCESS with the other values you were given...
Also if they give you the diameter the formula is C= d*pi that formula is the same as c=2*pi*r ..... Use either... just remember when they give you the radius.... the radius is half of the diameter... so take the radius times 2 and times that by pi When it asked for an approximation use 3.14 for pi. I'm sure you can do the rest by yourself. I hope this helped!
she can read a total of 0.83 pages a minute if she reads at the pace she was reading at because if you take the amount of pages she read (7.5) and you divide by the amout of minutes read (9) then you can see if she read at a constant rate she would read 0.83 pages a minute
