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There are 89 NRICH Mathematical resources connected to Time, you may find related items under Measuring and calculating with units.Broad Topics > Measuring and calculating with units > Time
Try this matching game which will help you recognise different ways of saying the same time interval.
Look at the changes in results on some of the athletics track events at the Olympic Games in 1908 and 1948. Compare the results for 2012.
Can you rank these sets of quantities in order, from smallest to largest? Can you provide convincing evidence for your rankings?
Can you put these mixed-up times in order? You could arrange them in a circle.
Can you put these times on the clocks in order? You might like to arrange them in a circle.
Can you place these quantities in order from smallest to largest?
These pictures show some different activities that you may get up to during a day. What order would you do them in?
Try this version of Snap with a friend - do you know the order of the days of the week?
This is a game for two players. Can you find out how to be the first to get to 12 o'clock?
Here's a chance to work with large numbers...
My measurements have got all jumbled up! Swap them around and see if you can find a combination where every measurement is valid.
These clocks have only one hand, but can you work out what time they are showing from the information?
Use the interactivity to move Pat. Can you reproduce the graphs and tell their story?
Two engines, at opposite ends of a single track railway line, set off towards one another just as a fly, sitting on the front of one of the engines, sets off flying along the railway line...
A bus route has a total duration of 40 minutes. Every 10 minutes, two buses set out, one from each end. How many buses will one bus meet on its way from one end to the other end?
A train leaves on time. After it has gone 8 miles (at 33mph) the driver looks at his watch and sees that the hour hand is exactly over the minute hand. When did the train leave the station?
On a digital clock showing 24 hour time, over a whole day, how many times does a 5 appear? Is it the same number for a 12 hour clock over a whole day?
A messenger runs from the rear to the head of a marching column and back. When he gets back, the rear is where the head was when he set off. What is the ratio of his speed to that of the column?
These clocks have been reflected in a mirror. What times do they say?
A simplified account of special relativity and the twins paradox.
Stuart's watch loses two minutes every hour. Adam's watch gains one minute every hour. Use the information to work out what time (the real time) they arrived at the airport.
On a digital 24 hour clock, at certain times, all the digits are consecutive. How many times like this are there between midnight and 7 a.m.?
During the third hour after midnight the hands on a clock point in the same direction (so one hand is over the top of the other). At what time, to the nearest second, does this happen?
If it takes four men one day to build a wall, how long does it take 60,000 men to build a similar wall?
How many times in twelve hours do the hands of a clock form a right angle? Use the interactivity to check your answers.
Alice's mum needs to go to each child's house just once and then back home again. How many different routes are there? Use the information to find out how long each road is on the route she took.
In this version of the story of the hare and the tortoise, the race is 10 kilometres long. Can you work out how long the hare sleeps for using the information given?
Mr. Sunshine tells the children they will have 2 hours of homework. After several calculations, Harry says he hasn't got time to do this homework. Can you see where his reasoning is wrong?
Follow the journey taken by this bird and let us know for how long and in what direction it must fly to return to its starting point.
July 1st 2001 was on a Sunday. July 1st 2002 was on a Monday. When did July 1st fall on a Monday again?
Nirmala and Riki live 9 kilometres away from the nearest market. They both want to arrive at the market at exactly noon. What time should each of them start riding their bikes?
Chandrika was practising a long distance run. Can you work out how long the race was from the information?
How far have these students walked by the time the teacher's car reaches them after their bus broke down?
Use the information to work out the timetable for the three trains travelling between City station and Farmland station.
What is the date in February 2002 where the 8 digits are palindromic if the date is written in the British way?
Liitle Millennium Man was born on Saturday 1st January 2000 and he will retire on the first Saturday 1st January that occurs after his 60th birthday. How old will he be when he retires?
Fifteen students had to travel 60 miles. They could use a car, which could only carry 5 students. As the car left with the first 5 (at 40 miles per hour), the remaining 10 commenced hiking along the road (at 4 miles per hour)...
My train left London between 6 a.m. and 7 a.m. and arrived in Paris between 9 a.m. and 10 a.m. At the start and end of the journey the hands on my watch were in exactly the same positions but the minute hand and hour hand had swopped places. What time did the train leave London and how long did the journey take?
These two challenges will test your time-keeping!
Can you explain why every year must contain at least one Friday the thirteenth?
On a clock the three hands - the second, minute and hour hands - are on the same axis. How often in a 24 hour day will the second hand be parallel to either of the two other hands?
Every day at noon a boat leaves Le Havre for New York while another boat leaves New York for Le Havre. The ocean crossing takes seven days. How many boats will each boat cross during their journey?
My cousin was 24 years old on Friday April 5th in 1974. On what day of the week was she born?
Which segment on a digital clock is lit most each day? Which segment is lit least? Does it make any difference if it is set to 12 hours or 24 hours?
Consider a watch face which has identical hands and identical marks for the hours. It is opposite to a mirror. When is the time as read direct and in the mirror exactly the same between 6 and 7?
Two trains set off at the same time from each end of a single straight railway line. A very fast bee starts off in front of the first train and flies continuously back and forth between the two trains. How far does Sidney fly before he is squashed between the two trains?
Do you know the rhyme about ten green bottles hanging on a wall? If the first bottle fell at ten past five and the others fell down at 5 minute intervals, what time would the last bottle fall down?
How many days are there between February 25th 2000 and March 11th?
This investigation explores using different shapes as the hands of the clock. What things occur as the the hands move.
Which times on a digital clock have a line of symmetry? Which look the same upside-down? You might like to try this investigation and find out!