Question

fatima wanted to know which brand of battery lasts longer - brand a, or brand b. she tested 16 batteries and recorded the number of hours each battery lasted. how much longer is the mean battery life of brand b compared with brand a? 0.43 hours 0.57 hours 1.75 hours 2.33 hours

Explanation:

Step1: Calculate mean of Brand A

Mean formula: $\frac{\sum_{i = 1}^{n}x_{i}}{n}$.
Sum of Brand A values: $27+14 + 21+17+20+15+12+24=150$.
Mean of Brand A: $\frac{150}{8}=18.75$.

Step2: Calculate mean of Brand B

Sum of Brand B values: $17+25 + 22+17+14+22+23+24=164$.
Mean of Brand B: $\frac{164}{8}=20.5$.

Step3: Find the difference

Difference: $20.5 - 18.75 = 1.75$.

Answer:

1.75 hours