Answer Happy

2022 has been a year marked by increasing inflation,
particularly the rising cost of gasoline that spiked at the onset
of the Russian invasion of Ukraine. For this project you will be
considering the type of gasoline purchased and the cost per gallon.
A simple random sample of 32 gasoline purchases was selected and
the data appears in the table on the next page. For “gas type”, R
represents Regular gas with an octane rating of 87, M represents
Mid-Grade gas with an octane rating of 89, P represents Premium gas
with an octane rating of 92, and D represents Diesel gas that is
restricted to use in diesel engines. The cost per gallon is rounded
to the nearest penny and the data recorded in dollars and
cents.
(A) Calculate and interpret a 95% confidence
interval for the mean cost of all gallons of gasoline purchased.
Complete the calculation and interpretation even if the assumptions
are violated.
Gas Type Cost per Gallon 4.08 R P 4.85 R 3.89 D 5.19 4.15 R R 4.19 M 4.49 R 4.03 Р 4.78 5.03 D R 4.06 R 3.79 P 4.82 4.42 M M 4.51 R 4.03 4.89 D R 3.97 R 4.16 4.68 Р ol D R R 4.57 3.98 4.65 4.03 4.88 R Р R 4.11 M D 4.64 5.01 3.89 R R M 4.23 4.56 4.24 R