What two numbers multiply to 84 but add to 40

Out of 50 students surveyed, 16 have a dog. based on these results, predict how many of the 280 students in the school have a dog.

Idon't want to fail summer school.the probabilities of contamination in medicine capsules due to the presence of heavy metals and different types of microbes are given in the table.the probability of capsule b having microbial contamination is (the same as, greater than, less than) the probability of capsule d having it.

Circle o has a circumference of approximately 44in what is the approximate length of the diameter d