Ahouse and a lot are worth $15,600. if the house is worth 12 times the value of the lot, find the value of each

Assume that y varies inversely with x. if y=1.6 when x=0.5 find x when y=3.2

Fracisco's game involves 3 green, 2 yellow, 4 red, and 3 black marbles. if he randomly draws three marbles from the bag, without replacement, what is the probability that he will draw yellow, and then red, and then black? a)1/192 b)1/72 c)3/220 d)1/55

Ineed some on this. not sure how to solve.