Wow, i wonder why they were lifting a large boulder? They should put it down they could get hurt!!
Answer:
a) Sample mean: 48.71
Sample median: 48.3
Sample variance: 5.41
Sample standard deviation: 2.37
Step-by-step explanation:
a) Sample mean:

Sample median: M=48.3
Note: I order the data increasingly and take the value N / 2 = 40. In this way there are 39 values above and 39 values below the median.
Sample variance:

Sample standard deviation

b)
Since its 3/4 serving and there are 18 pancakes
18 divided by 3/4
just find the reciprocal (switch the denominator and numerator) and change divide to multiply
18 x 4/3 = 24 servings
the reason being for multiplying the reciprocal: there is a rule stating that whenever you divide something by a fraction, you change the divide sign to a multiplying sign and flip the flip the digits in the numerator and denominator section in the fraction (basically the fractions reciprocal)
or another way of doing it is
3/4 = 0.75
18/0.75 = 24
but you'll likely to need a calculator for that
The answer is 9bt if you gave me the rest of the question I would maybe be able to get the real answer.