Learning math The Core Plus Mathematics Project (CPMP) is an innovative approach to teaching Math-ematics that engages students in group investigations and mathematical modeling. After field tests in 36 highschools over a three-year period, researchers comparedthe performances of CPMP students with those taughtusing a traditional curriculum. In one test, students had tosolve applied Algebra problems using calculators. Scoresfor 320 CPMP students were compared to those of a control group of 273 students in a traditional Math pro-gram. Computer software was used to create a confidence interval for the difference in mean scores. (Journal forResearch in Mathematics Education, 31, no. 3[2000])Conf level: 95% Variable: Mu(CPMP) – Mu(Ctrl)Interval: (5.573, 11.427)a) What’s the margin of error for this confidenceinterval?b) If we had created a 98% CI, would the margin of errorbe larger or smaller?c) Explain what the calculated interval means in context.d) Does this result suggest that students who learnMathematics with CPMP will have significantlyhigher mean scores in Algebra than those in traditionalprograms? Explain.

Definition Definition Measure of central tendency that is the average of a given data set. The mean value is evaluated as the quotient of the sum of all observations by the sample size. The mean, in contrast to a median, is affected by extreme values. Very large or very small values can distract the mean from the center of the data. Arithmetic mean: The most common type of mean is the arithmetic mean. It is evaluated using the formula: μ = 1 N ∑ i = 1 N x i Other types of means are the geometric mean, logarithmic mean, and harmonic mean. Geometric mean: The nth root of the product of n observations from a data set is defined as the geometric mean of the set: G = x 1 x 2 ... x n n Logarithmic mean: The difference of the natural logarithms of the two numbers, divided by the difference between the numbers is the logarithmic mean of the two numbers. The logarithmic mean is used particularly in heat transfer and mass transfer. ln x 2 − ln x 1 x 2 − x 1 Harmonic mean: The inverse of the arithmetic mean of the inverses of all the numbers in a data set is the harmonic mean of the data. 1 1 x 1 + 1 x 2 + ...