Final answer:
The approximate cost to build the Flying Scotsman steam engine in 1923 was £8,000, which is obtained by dividing the restoration cost of £4 million by 500.
Step-by-step explanation:
The cost of building the Flying Scotsman steam engine in 1923 can be estimated by dividing the cost of its restoration by the multiple stated in the question. According to the information provided, the restoration cost approximately £4 million, which was around 500 times the original building cost. To find the original cost, we will therefore divide £4 million by 500.
£4,000,000 ÷ 500 = £8,000
So, the approximate cost to build the steam engine in 1923 was £8,000. Hence, the correct answer is B) £8,000.