Take this Exam: T Level Digital: Data and Analysis | Zestly

Question 1

Thirlmere Brewing has monthly sales figures for the last twenty-four months and wants to show whether sales are rising or falling over that period. Which chart is most suitable?

Accepted Answer

A line chart, because it shows a value changing over a continuous period of time.

Answer

A pie chart, because it shows how the total is divided up.

Answer

A single bar showing the total of all twenty-four months.

Answer

A scatter chart comparing sales with the number of staff.

Question 2

Selby Leisure finds that in the weeks when its ice cream sales are highest, admissions to its outdoor pool are also highest. What can the operator properly conclude?

Accepted Answer

That the two move together, and that something else, such as the weather, may be driving both.

Answer

That selling ice cream causes people to use the pool.

Answer

That pool admissions cause ice cream sales.

Answer

That the two figures must have been recorded incorrectly.

Question 3

At Ravensworth Health, twelve per cent of records have a blank in the age field, and an analyst deletes every row with a blank. What is the risk of this action?

Accepted Answer

If the blanks are not spread evenly across the records, deleting them removes one kind of person more than another and biases the result.

Answer

Deleting rows always makes the file too small to analyse.

Answer

The deleted rows cannot be recovered from the backup.

Answer

Ages are never needed for analysis anyway.

Question 4

Grimsargh Couriers reports a mean delivery time of three days. In fact, about half its parcels arrive in one day and about half in five. What does the mean fail to show?

Answer

The mean has been calculated incorrectly.

Answer

The mean is too small a number to be useful.

Answer

The spread: two very different groups of customers are being averaged into a figure that describes almost nobody's actual experience.

Answer

The total number of parcels delivered.

Question 5

A form at Alnwick Insurance refuses a date of birth that falls in the future. What is this check, and what is its limitation?

Answer

It is validation, which checks that an entry is possible, and it cannot catch a date that is possible but simply not the customer's real date of birth.

Answer

It is verification, and it proves the date is correct.

Answer

It is validation, and it makes a separate check against the customer's documents unnecessary.

Answer

It is encryption, and it protects the date from being read.