标题: 几道prepare 数学题。。。 [打印本页] 作者: 甜心俏女巫 时间: 2010-3-11 22:56 标题: 几道prepare 数学题。。。 1。A set of 15 different integers has a median of 25 and a range of 25.What is the greatest possible integer that could be in this set? A.32 B.37 C.40 D.43 E.50
2. The rate of a certain chemical reaction is directly proportional to the square of the concentration of chemical A present and inversely proportional to the concentration of chemical B present. If the concentration of chemical B is increased by 100 percent, which of the following is closet to the percent change in the concentration of chemical A required to keep the reaction rate unchanged? A 100% decrease B.50% decrease C. 40% decrease D.40% increase E.50% increase
3. In a survey of students, each student selected from a list of 12 songs the 2 songs that the student liked best. If each song was selected 4 times, how many students were surveyed? A 96 B 48 C 32 D 24 E 18