If the probability of flipping heads is 0.70, the probability of flipping tails is 0.30.
To find probability, you multiply the probability of each factor together:
P = 0.7 * 0.3
P = 0.21 <em>or</em><em> </em>21%
To find the circumference of a circle you have to multiple the radius by 2 and also by pi. So, to find the radius when given just the circumference, who have to do the reverse operation and divide the circumference by 2 and also by pi to get the answer of 22.92993631, which you could of course round.
