Patios can be made by mixing cubic meters of cement, gravel, and stones in the ratio 9:4:6. How much gravel is needed to make 209 cubic meters of patio?

Achemist has 200 ml of a 10% sucrose solution. she adds x ml of a 40% sucrose solution. the percent concentration, y, of the final mixture is given by the rational function: the chemist needs the concentration of the final mixture to be 30%. how many milliliters of the 40% solution should she add to the 10% solution to get this concentration?

Aplane intersects a pris paralel to the base of the prism. the cross section is a polygon wth eight sides. how many sides does the base of the prism have? a. 10 b. 8 c. 7 d. 9

Gabrielle's age is two times mikhail's age. the sum of their ages is 84. what is mikhail's age?