Numerical exercise · ~1 min a run · free
Speed, Distance and Time
Work a leg in your head: speed, distance or time.
Session mode
Difficulty
Auto sets the level from your recent results: up when you are acing it, down when it is too hard.
How to play
- 1Read the leg: you are given two of speed, distance and time.
- 2Work out the missing value in your head.
- 3Pick the matching option; keep an eye on your time.
See a worked example
Ground speed 420 kt, how far in 25 minutes? Do not reach for distance = speed x time in hours. The transferable move is to convert the speed into nautical miles per minute once, by dividing by 60: 420 becomes 7 NM per minute. Then 7 x 25 = 175 NM. Every leg problem, in either direction, becomes one easy multiplication or division after that step, and it is the same number pilots use in the air. The trap is the option built from 420 x 25 with the decimal point moved, so check the size of your answer against the minutes: 25 minutes is under half an hour, so the distance must be under half of 420.
Convert between ground speed, distance and time the way you would in the cruise. Given any two, find the third, fast and without a calculator.
About this test
About this test
What this test measures
This measures applied numerical reasoning with the speed, distance and time relationship that underpins every navigation problem. It is the single most useful piece of mental maths a pilot owns, since groundspeed, ETA and fuel all flow from it.
How to improve your score
- Memorise the triangle, distance equals speed times time, and rearrange it instantly rather than re-deriving it each time.
- Get fluent with the 60 rule: at 60 knots you cover a mile a minute, then scale from there.
- Always sanity-check the unit and the order of magnitude before trusting the number.
Good to know
Good to know
The 60-to-1 shortcut
Distance in nautical miles equals ground speed in knots times minutes, divided by 60. At 420 kt for 20 minutes that is 420 x 20 / 60 = 140 NM. Learning this one line solves most legs without long division.Keep your units honest
Most marks are lost to mismatched units, not arithmetic. Decide up front whether you are working in minutes or hours, and write the unit next to each number. Values are usually chosen so the answer comes out clean.
Frequently asked questions
What is the key formula?
What is the key formula?
How do I handle minutes?
How do I handle minutes?
Is this like the real selection maths?
Is this like the real selection maths?
Training for an airline assessment?
The SkyStudy ATPL question bank is built for EASA ATPL exam preparation, with timed mock exams, spaced repetition and analytics across every subject. Free to start, no card needed.