Sarah wants to determine if there is a correlation between the number of hours students spend revising and their scores on a standardized mathematics test.
She calculates the product moment correlation coefficient for a random sample of 50 students and finds r=0.25r = 0.25r=0.25.
Carry out a suitable test to investigate Sarah's belief at a 5% level of significance.
State clearly
316 exam-style questions on OCR A Level Maths 2.5 Statistical Hypothesis Testing, covering 2.5.1 The language of hypothesis testing, 2.5.2 Hypothesis test for a binomial proportion, 2.5.3 Inference and significance level, 2.5.4 Sample mean as a random variable (A-level only), 2.5.5 Hypothesis test for the mean of a normal distribution (A-level only), 2.5.6 Pearson's product-moment correlation coefficient, and 2.5.7 Hypothesis test using Pearson's coefficient (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.