Apositive integer with exactly two different divisors greater than 1 must be(a) a prime(b) an even integer(c) a multiple of 3(d) the square of a prime(e) the square of an odd integer

On a string instrument, the length of a string varies inversely as the frequency of its vibrations. an 11-inch string has a frequency of 400 cylces per second. find the frequency of a 10-icnch string.

Jack did 3/5 of all problems on his weekend homework before sunday. on sunday he solved 1/3 of what was left and the last 4 problems. how many problems were assigned for the weekend?

What is the anwers for 9+2x=5x-3-x