Solve each problem. 10. The sum of two numbers is 23. If one of the numbers is halved, the sum will
become 17. What are the numbers?
11. The perimeter of a rectangle is 60 cm. The length is four times the width. What
are the length and the width of the rectangle?
Write a system of equations to model each situation. Solve by any method.
12. Sarah is 25 years older than her son Gavin. In ten years, Sarah will be twice
Gavin's age. How old are Sarah and Gavin now?
Yen chemist is mixing a solution that is 2% acid and another solution that is 8%
acid. She needs to make 75 mL of a solution that is 5% acid. How much of each
solution should she use?

Equation for the calculation double 2 and then add 5

In the diagram, gef and hef are congruent. what is the value of x

Nthe opening scene of the movie raiders of the lost ark, indiana jones replaces a golden statue with a bag of sand. the platform on which the statue is placed is designed to detect the mass of the statue. if the bag of sand has a different mass than the statue, then a mechanism triggers and destruction ensues. the density of gold is about 20\text{ g/cm}^320 g/cm 3 20, space, g, slash, c, m, start superscript, 3, end superscript. the density of sand can be estimated at 2.5\text{ g/cm}^32.5 g/cm 3 2, point, 5, space, g, slash, c, m, start superscript, 3, end superscript. the gold statue can be modeled as a cylinder with height 25\text{ cm}25 cm25, space, c, m and radius 8\text{ cm}8 cm8, space, c, m. in terms of \piπpi, what is the mass of sand indiana jones needs to avoid triggering the mechanism?