It is believed that the average amount of money spent per u. s. household per week on food is about $98, with standard deviation $10. a random sample of 100 households in a certain affluent community yields a mean weekly food budget of $100. we want to test the hypothesis that the mean weekly food budget for all households in this community is higher than the national average. are the results significant at the 5% level?

yes, we can reject the hypothesis

Step-by-step explanation:

The null hypothesis  

H0 = mean weekly food budget for all households in this community is $98

Let´s find z

z= (x – mean) / standard deviation / √sample size

z = (100 – 98) / 10 / √100

z = 2

Using  a Z table we can find probability  

P (z>2) = 0.0228

Since P < α , results are significant and we can reject the hypothesis

10.416 meters per second

step-by-step explanation:

distance=1 00 meters

time= 9.6 seconds in decimal form or 9 3/5 as a mixed number

average speed= 100/9.6

=10.416 meters per second or 10 52/125 as a mixed number.