Hint: These are the first letters of the words: T, T, H, D, W, L, H, W, C, N
TEL + ESC + OPE = TELESCOPE
TIM + ETA + BLE = TIMETABLE
HAI + RBR + USH = HAIRBRUSH
DIF + FER + ENT = DIFFERENT
WAT + ERF + ALL = WATERFALL
LIG + HTN + ING = LIGHTNING
HEA + DLI + GHT = HEADLIGHT
WHI + RLW + IND = WHIRLWIND
CAR + TIL + AGE = CARTILAGE
NEW + SAG + ENT = NEWSAGENT
Last week I travelled from London to Leeds, which is a distance of 174 miles.
I started at 9.15am and completed the journey with an average speed of 40 miles per hour.
On the way back, in the evening, I travelled exactly the same route, starting at 5.15pm. The traffic was light and I completed the journey with an average speed of 60 miles per hour.
What was the overall average speed for round trip?
Q1 can't have A as its answer (otherwise it would contradict itself).
If Q1's answer was C (meaning Q4's answer was A), then Q3's answer would be C. However, Q2's answer should now be A, but this isn't allowed by Q1 (as Q4 is the first answer with A). This is a contradiction.
Therefore Q1's answer is B (meaning Q3's answer is A).
For Q2's answer to be C, Q4's answer would have to be A, which would contradict Q4. Therefore Q2's answer is B, making Q4's answer B.