ISTQB Certified Tester Advanced Level – Test Analyst (CTAL-TA) — Question 69

Sell-It-Cheap salesrooms organises general and specialist sales where items are sold to the highest bidder. There is a sliding scale of commission charges, based on the price of items sold, with lower-priced items attracting a higher percentage. All items sold have a price in multiples of £1.
Items sold for £150 or less attract a flat-rate fee of £7.00, items otherwise sold for less than £500 have a fee of 6% of the price realised. Items otherwise sold for less than £1000 have a 4.5% fee, with items otherwise sold for less than £5000 having a 3.5% fee. Any items sold for £5000 or more have a 3% fee.
Following customer feedback, Sell-It-Cheap have decided to change one of the existing commission bandings, with items sold between £500 and £749 having a 5.5% fee, and items otherwise less than £1,000 having a 4.5% fee.
What tests would be appropriate to test this change in commission bandings, using the 2-point boundary value analysis technique?

Answer options

Correct answer: C

Explanation

The correct answer is C because it includes tests at the boundaries relevant to the changed commission structure: £499 (below the first boundary), £500 (exactly at the first boundary), £749 (just below the second boundary), £750 (at the second boundary), £999 (just below the third boundary), and £1000 (exactly at the third boundary). Options A and D do not cover all necessary boundaries, and option B incorrectly assumes that existing tests suffice without accounting for the changes.