Tensar Summer Quiz

by Andrew Lees, on 30-Jul-2020 04:06:47

It is summertime, the sun is shining (well in some places) and Andrew is back with a gin and tonic in hand. He has a new challenge in the form of his summer quiz to get us all thinking.

The quiz is based around maths and logic, with questions themed on construction and civil engineering. No civil engineering prior knowledge is needed so why not share with colleagues, friends, and family!

The answers will be revealed in three weeks’ time. Good luck!

Tensar Ground Coffee Episode 21 - The Tensar Summer Quiz


  1. Two ambitious site investigation companies, one located in UK and one in New Zealand, decide to construct a borehole between their respective countries through the centre of the Earth. The UK team sink their borehole at an astonishing constant rate of 20km per day while the NZ team go even faster at 30km per day. Given that the diameter of the Earth between them is 12,730 km and that they head in a straight line towards each other, how long does it take for the holes to meet? And at what distance from the UK does the meeting occur?

  2. Tarquell and Sandra are preparing to go back to their construction jobs after a summer break by buying some PPE from the same shop. Tarquell buys 3 high-visibility vests and 2 pairs of goggles for £36 and Sandra buys 2 high-visibility vests and 4 pairs of goggles for £40. How much is one pair of goggles?

  3. Mary-Ann is an environmental engineer taking water samples from three wells for monitoring purposes. She takes one sample from Well A, two samples from Well B and three samples from Well C. When she returns to the laboratory, she gathers the six sample bottles together and randomly selects three for testing. What is the probability that each well has contributed a sample to the test?

  4. 16 years ago the Federation of Piling Specialists (FPS) was five times as old as the Civil Engineering Contractors Association (CECA). 8 years ago CECA was one-third the age of the FPS. When were the FPS and CECA founded (without looking it up)?

  5. An innovative local authority decides to procure construction work by means of a game show. On the show there are three closed doors. Behind one is a lucrative construction contract, while the others conceal only a bag of potatoes. The hopeful contractor selects a door, which remains closed. The head of procurement at the local authority, knowing where the lucrative contract is hidden, opens one of the remaining two doors to reveal a bag of potatoes. The contractor is given the option to switch doors or to stick with their original choice. What should the contractor do in order to have the best chance of winning the lucrative contract?

  6. A 400-metre long train is approaching a 100-metre long tunnel at a constant 80km/h. How long does it take for the entire train to pass through the tunnel?

  7. Three people buy a box of face masks at a pharmacy. They pay £30 to the pharmacist and leave the shop with the box. The pharmacist realises that the box of face masks actually costs £25 and gives £5 to her assistant to return to the customers. The assistant runs out of the shop to catch up with them. On the way, he decides that £5 will be difficult to split three ways, so he pockets £2 and gives £1 to each person. Now each person paid £10 and got back £1, so they paid £9 each, totalling £27. The assistant has £2, totalling £29. Where is the missing £1?

  8. A rope swing hangs vertically down so that the end is 30cm from the ground and 120cm from the tree. If the swing is pulled across to touch the tree, it is 50cm from the ground. How long is the rope?
    Blog Summer Quiz Q8

  9. An electrically powered van arrived at Tensar’s factory in Blackburn, UK to pick up a roll of geogrid to be delivered to a construction site. After receiving a full battery charge it departed, travelling at a steady 40km/h towards its destination. At that speed it was losing 10% of charge for every 20km travelled. It was a hot day, so the driver had the air-conditioning on which drained the battery a further 5% per hour. The battery was flat when the van arrived at the site and only just made it. How far was the site from the Blackburn factory?

  10. You have the misfortune to sit an exam in a room with an unreliable clock. It gains exactly 12 minutes every hour. The exam was intended to last 3 hours but if the invigilator relied on the clock in the room, how long did you actually have to complete the exam?