One-sample t-tests Problem set B Answers

1. (a) H0: μ = 450, H1: μ < 450
2. (b) H0: μ = 8.4, H1: μ > 8.4
3. (c) H0: μ = 35, H1: μ ≠ 35

t = 3.37, p = 0.00598; reject H0

t = −3.34, p = 0.00780; reject H0

t = −2.20, p = 0.0638; do not reject H0

t = −2.57, p = 0.0167; reject H0

1. (a) H0: μ = 6, H1: μ > 6
2. (b) t = 1.84, p = 0.0519
3. (c) There is sufficient evidence, at the 10% significance level, that the mean honey yield per hive has increased.
4. (d) The honey yield per hive is normally distributed.

1. (a) t = −3.27, p = 0.00170
2. (b) There is sufficient evidence, at the 1% significance level, that the mean journey time is lower than 8.0 minutes.

1. (a) There is sufficient evidence, at the 5% significance level, that the mean time spent on homework has decreased.
2. (b) There is insufficient evidence, at the 1% significance level, that the mean time spent on homework has decreased.

1. (a) t = −1.34, p = 0.214. There is insufficient evidence, at the 5% significance level, that the mean mass is not 250 g.
2. (b) The masses of packets are normally distributed.

1. (a) H0: μ = 4, H1: μ > 4
2. (b) t = 2.12, p = 0.0244
3. (c) There is sufficient evidence, at the 5% significance level, that the mean journey time has increased.