Sam is 3 times as old as rob. if 15 is subtracted from sam's age and 13 is added to rob's age, their ages will be equal. how old is each now?

Graph red beads cost $1 an ounce and gold beads cost $3 an ounce. juanita wants to purchase a 12-ounce mixture of red and gold beads that she can sell for $2 an ounce. the solution of the system shows the number of beads needed for juanita to break even. x + y = 12, x + 3y = 24 how many ounces of red beads will juanita buy to break even? how many ounces of gold beads will she buy?

Acomputer store bought a program at a cost of $10 and sold it for $13. find the percent markup

3.4a=57.8 what is the the value of a