Scores on a math midterm are distrubted under a standard normal curve. A randomly selected student had a score of 55, which represented a z score of -2.35. If the mean for the exam was 76, determine the standard deviation for the exam

Question

kropot72 · Answer

$$z=\frac{X-\mu}{\sigma}$$
$$-2.35=\frac{55-76}{\sigma}$$
$$\sigma=\frac{55-76}{-2.35}=?$$
Can you calculate the value of sigma (the standard deviation) now?

kropot72 · Answer

$$\frac{55-76}{-2.35}=\frac{-21}{-2.35}=\frac{21}{2.35}=?$$

kropot72 · Answer

@Murry Are you there? Do you have a calculator?

anonymous · Answer

Yes i have a calculator