In class of remedial English taught by lecture method, 52 out of 75 students completed the course with a passing grade. In same course with computer-assisted instruction, 69 out of 95 completed course with passing grade. At .05 level, is there a significant difference in passing rates for the 2 different methods of instruction?

**Solution: **We use z-test for proportions to test

_{}

The z-statistics is computed as

_{}

where

_{}, _{}, _{}

Replacing the values at the z-statistics we get that

_{}

The critical values for the 0.05 level are_{}. Therefore, we cannot reject the null hypothesis, which means that ** we don’t have enough evidence to claim** that there is a significant difference in passing rates for the 2 different methods of instruction

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