Step-by-step explanation:
Given precision is a standard deviation of s=1.8, n=12, target precision is a standard deviation of σ=1.2
The test hypothesis is
H_o:σ <=1.2
Ha:σ > 1.2
The test statistic is
chi square = 
=
=24.75
Given a=0.01, the critical value is chi square(with a=0.01, d_f=n-1=11)= 3.05 (check chi square table)
Since 24.75 > 3.05, we reject H_o.
So, we can conclude that her standard deviation is greater than the target.
Answer: the hourly fee for the rototiller is $3
Step-by-step explanation:
Let h represent the hourly fee for renting the rototiller.
The rental company charged an initial fee of $43 with an additional fee per hour. Assuming that they rented the rototiller for x hours. This means that if they rented the rototiller for x hours, the total amount that they would pay is
43 + hx
If they paid $64 after renting the rototiller for 7 hours, the equation that models this problem would be
43 + 7h = 64
7h = 64 - 43 = 21
h = 21/7 = $3
Answer:
4,3
Step-by-step explanation:
4,3
Answer:
y = 1/20 x + 5
Step-by-step explanation:
Let the height of the sand dune after x years be represented by the equation
y = mx+c where;
m is the rate at which the hills is eroding
c is the height of the dunes above the sea
If The hill is eroding at a rate of 1 foot per 20 years,then the rate of eroding per year will be;
1foot = 20years
m = 1year
Cross multiply
20m = 1
m = 1/20 foot/yr...
c = 5foot
Substitute into the formula:
y = 1/20 x + 5
Hence the equation that represent the situation is y = 1/20 x + 5