Practice

Practise until it sticks

Choose a topic, a skill or a difficulty. Calculation exercises have new versions with fresh numbers once you have solved them, so you can practise the method rather than memorise an answer.

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Application, difficulty 2 of 3

Did the groups start equal?

Not started

Now compute the mean previous-year score (prior_score) for tutored and untutored students (2 decimal places). Did the two groups start out equal?

Data: student_scores · Open in the lab to explore and calculate.