What is 30% in decimal form

The probability that an adult possesses a credit card is .70. a researcher selects two adults at random. by assuming the independence, the probability that the first adult possesses a credit card and the second adult does not possess a credit card is:

Find the condition that the zeros of the polynomial f(x) = x^3+3px^2+3px+r may be in a.p.

Which equation can be solved to find x the measure of jk in the apex