1. First, we solve the z-score of 52.6
z-score = (52.6 – 45)/81 = 0.0938
percentile value = 53.7
Therefore, the probability is 100-53.7 = 46.3%
2. We solve again for the z-score of 43
z-score = (43 – 45)/81 = -0.0247
percentile value = 49%
Thus, 49% of students scored 49%
3. Z-score of 49,
z-score = (49-45)/81 = 0.04938
4. If z-score is 1.5,
1.5 = (mean – 45)/81 = 166.5