Twelve of the last 16 winners of the school science fair have been seventh grade students. Mona placed 3 red marbles and 1 green marble in a bag to create a simulation to predict whether future science fair winners will be seventh graders. According to Mona's model, what is the probability that the next 4 winners will all be seventh grade students? StartFraction 3 over 16 EndFraction StartFraction 81 over 256 EndFraction Three-fourths StartFraction 7 over 8 EndFraction

Naomi’s parents want to have 50,000, saved for her college education, if they invest 20000 today and earn 7% interest compound annually, about how long will it take them to save 50 thousand

Quick! a survey of 57 customers was taken at a bookstore regarding the types of books purchased. the survey found that 33 customers purchased mysteries, 25 purchased science fiction, 18 purchased romance novels, 12 purchased mysteries and science fiction, 9 purchased mysteries and romance novels, 6 purchased science fiction and romance novels, and 2 purchased all three types of books. a) how many of the customers surveyed purchased only mysteries? b) how many purchased mysteries and science fiction, but not romance novels? c) how many purchased mysteries or science fiction? d) how many purchased mysteries or science fiction, but not romance novels? e) how many purchased exactly two types of books?

Which of the following pair(s) of circles have las a common external tangent? select all that apply. a and b a and c b and c