Mark and don are planning to sell each of their marble collections at a garage sale. if don has 2 more than 3 times the number of marbles mark has, how many does each boy have to sell if the total number of marbles is 78 ?

Brian has an unlimited number of cents (pennies), nickels, and dimes. in how many different ways can he pay 1414cents¢ for a chocolate mint?

Anew test for ra is being developed. the test is administered to 750 patients with ra and 750 without ra. for the sake of the question, assume the prevalence of ra in this population is 50%. of the 750 patients with ra, 575 have a positive result. of the 750 patients without ra, 150 have a positive result. what is the positive predictive value of the new test? a575/(575+150) b. 600/(600+ 150) c. 575/(575+125) d. 600/(600+ 125)

Step by step explanation pls for 10 pts the length of a rectangular board is 3 feet less than twice its width. a second rectangular board is such that each of its dimensions is the reciprocal of the corresponding dimensions of the first rectangular board. if the perimeter of the second board is one-fifth the perimeter of the first, what is the perimeter of the first rectangular board?