Question

The number of minutes customers wait at the payment counters at two supermarkets is recorded as under:

Mega Super Market:	3	2	4	6	7	5	4	5	8	4	7	5
Deluxe Super Market	2	6	3	5	4	8	7	8	6	6

Which supermarket had the least mean waiting time ?

Answer 1

Step $1:$ Finding mean for mega supermarket

Mega Super Market:	3	2	4	6	7	5	4	5	8	4	7	5
Deluxe Super Market	2	6	3	5	4	8	7	8	6	6

Since, $Mean=\frac{Sumofallobservations}{TotalNumberofObservations}.....\left(i\right)$

Now, total number of observation $=12$ [ From the given data]

sum of all observation $=3+2+4+6+7+5+4+5+8+4+7+5=55$

So, Mean $=\frac{55}{12}=4.58$ [Using equation (i)]

Hence, mean of the mega supermarket is $4.58$

.Step $2:$ Finding mean for mega supermarket

Mega Super Market:	3	2	4	6	7	5	4	5	8	4	7	5
Deluxe Super Market	2	6	3	5	4	8	7	8	6	6

Since, $Mean=\frac{Sumofallobservations}{TotalNumberofObservations}.....\left(i\right)$

Now, total number of observation $=10$ [ From the given data]

sum of all observation $=3+2+4+6+7+5+4+5+8+4+7+5=55$

So, Mean $=\frac{55}{10}=5.5$ [Using equation (i)]

Hence, mean of the mega supermarket is $5.5$.

Hence, mega supermarket had the least mean waiting time , that is $4.58$ minutes.