An alloy of tin is 15% tin weigh 20 pounds. A second alloy is 10% tin. how much pounds of the second alloy must be added to the first to get a 12% mixture

Three segments of lengths 25 cm, 37 cm, and 62 cm will form a triangle.

If the perimeter of the rectangle is 32cm and the area is 55cm2, what are the dimensions of the rectangle?

How do I I solve this equation? -18 = x/3 + 3

Which of the following us the solution to 6 | x-9 | > 12?

Solve each algebraically |x|=12 |x|=1/2 |x|-6=4 5+|x|=14 3|x|=24 |x+3|=10

A bag contains five red marbles and four blue marbles. A second bag contains four green marbles and five yellow marbles.

Radium-226, a common isotope of radium, has a half-life of 1,620 years. How many grams of a 120-gram sample will remain after t years?

the combined length of 3 pieces of a board is 147 inches. the lengths of the pieces are in the ratio 5:7:9. what is the difference in inches between the longest piece and the shortest piece?

Determine the radius of a circle with a circumference of 14 pi inches

Jonathan collects postcards and stamps. The number of postcards in his collection is 12 more than the number of stamps. He has 39 postcards in all. If Jonathan has x stamps, which equation represents this situation and how many stamps does he have?