138 x ? = 75
? = 75/138 = 0.544(3sf)
so about 54.35% (2dp) decrease
Answer:
a)

b)

Step-by-step explanation:
We have to build appropriate null and alternate hypothesis for the given scenarios.
a) Population mean, μ = $62,500 per year
The market research wants to find whether the mean household income of mall shoppers is higher than that of the general population.

We would use one-tail(right) test to perform this hypothesis.
b) Population mean, μ = 2.6 hours
The company want to know the average time to respond to trouble calls is different or not.

We would use two-tail test to perform this hypothesis.
Answer:
2
Step-by-step explanatio: look at the chart
Answer:
66 cm^2
Step-by-step explanation:
12*6=72 cm^2 and to find the missing pience of the rectangle you multiply 3*2= 6 cm^2.
72 - 6 = 66