9. Angola High School sold three times as many children's tickets as adult tickets for the school play. The total amount collected was
$357.50. Children's tickets cost $1.50 each, and adult tickets cost
$2.00 each. Which system of equations below could be used to
determine c, the number of children's tickets, and a, the number of
adult tickets, that were sold?

Aroulette wheel has 38 slots in which the ball can land. two of the slots are green, 18 are red, and 18 are black. the ball is equally likely to land in any slot. the roulette wheel is going to be spun twice, and the outcomes of the two spins are independent.the probability that it lands one time on red and another time on black in any order is(a) 0.5 (b) 0.25 (c) 0.4488 (d) 0.2244