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#### Resources tagged with Time similar to Paradoxes:

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### There are 67 results

Broad Topics > Measures and Mensuration > Time

##### Stage: 2 and 3

A paradox is a statement that seems to be both untrue and true at the same time. This article looks at a few examples and challenges you to investigate them for yourself.

### Friday 13th

##### Stage: 3 Challenge Level:

This month there is a Friday the thirteenth and this year there are three. Can you explain why every year must contain at least one Friday the thirteenth?

### Decimal Time

##### Stage: 3 Challenge Level:

Use the clocks to investigate French decimal time in this problem. Can you see how this time system worked?

##### Stage: 3 Challenge Level:

Great Granddad is very proud of his telegram from the Queen congratulating him on his hundredth birthday and he has friends who are even older than he is... When was he born?

### An Unhappy End

##### Stage: 3 Challenge Level:

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...

### Rule of Three

##### Stage: 3 Challenge Level:

If it takes four men one day to build a wall, how long does it take 60,000 men to build a similar wall?

### John's Train Is on Time

##### Stage: 3 Challenge Level:

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?

### Calendars

##### Stage: 1, 2 and 3

Calendars were one of the earliest calculating devices developed by civilizations. Find out about the Mayan calendar in this article.

### On What Day Did it Happen?

##### Stage: 1, 2 and 3

Read this article to find out the mathematical method for working out what day of the week each particular date fell on back as far as 1700.

### Digital Times

##### Stage: 3 Challenge Level:

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?

### Thousands and Millions

##### Stage: 3 Challenge Level:

Here's a chance to work with large numbers...

### Ten Green Bottles

##### Stage: 2 Challenge Level:

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?

### Crossing the Atlantic

##### Stage: 3 Challenge Level:

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?

### Hello Again

##### Stage: 3 Challenge Level:

Anne completes a circuit around a circular track in 40 seconds. Brenda runs in the opposite direction and meets Anne every 15 seconds. How long does it take Brenda to run around the track?

### The Hare and the Tortoise

##### Stage: 2 Challenge Level:

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?

### Slow Coach

##### Stage: 2 Challenge Level:

How many of this company's coaches travelling in the opposite direction does the 10 am coach from Alphaton pass before reaching Betaville?

### On Time?

##### Stage: 1, 2 and 3

This article explains how Greenwich Mean Time was established and in fact, why Greenwich in London was chosen as the standard.

### Two Clocks

##### Stage: 2 Challenge Level:

These clocks have only one hand, but can you work out what time they are showing from the information?

### Sweeping Hands

##### Stage: 2 Challenge Level:

Use your knowledge of angles to work out how many degrees the hour and minute hands of a clock travel through in different amounts of time.

### Making Maths: Make a Pendulum

##### Stage: 2 and 3 Challenge Level:

Galileo, a famous inventor who lived about 400 years ago, came up with an idea similar to this for making a time measuring instrument. Can you turn your pendulum into an accurate minute timer?

### Buses

##### Stage: 3 Challenge Level:

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?

### The Time Is ...

##### Stage: 2 Challenge Level:

Can you put these mixed-up times in order? You could arrange them in a circle.

### A Flying Holiday

##### Stage: 2 Short Challenge Level:

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.

### The New Millennium: When Did it Begin?

##### Stage: 2

Not everybody agreed that the Third Millennium actually began on January 1st 2000. Find out why by reading this brief article.

### Time and Tide

##### Stage: 1, 2 and 3 Challenge Level:

What can you say about when these pictures were taken?

### Home Time

##### Stage: 2 Challenge Level:

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.

### Working with Dinosaurs

##### Stage: 2

This article for teachers suggests ways in which dinosaurs can be a great context for discussing measurement.

### Timing

##### Stage: 2 Short Challenge Level:

These two challenges will test your time-keeping!

### Train Timetable

##### Stage: 2 Challenge Level:

Use the information to work out the timetable for the three trains travelling between City station and Farmland station.

### A History of Astronomy

##### Stage: 2

Astronomy grew out of problems that the early civilisations had. They needed to solve problems relating to time and distance - both mathematical topics.

### Walk and Ride

##### Stage: 2 and 3 Challenge Level:

How far have these students walked by the time the teacher's car reaches them after their bus broke down?

### Right Time

##### Stage: 3 Challenge Level:

At the time of writing the hour and minute hands of my clock are at right angles. How long will it be before they are at right angles again?

### Bike Ride

##### Stage: 2 Challenge Level:

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?

### Hands Together

##### Stage: 3 Challenge Level:

Sometime during every hour the minute hand lies directly above the hour hand. At what time between 4 and 5 o'clock does this happen?

### Speedy Sidney

##### Stage: 3 Challenge Level:

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. . . .

### A Calendar Question

##### Stage: 2 Challenge Level:

July 1st 2001 was on a Sunday. July 1st 2002 was on a Monday. When did July 1st fall on a Monday again?

### Millennium Man

##### Stage: 2 Challenge Level:

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?

### N Is a Number

##### Stage: 3 Challenge Level:

N people visit their friends staying N kilometres along the coast. Some walk along the cliff path at N km an hour, the rest go by car. How long is the road?

### Do You Measure Up?

##### Stage: 2 Challenge Level:

A game for two or more players that uses a knowledge of measuring tools. Spin the spinner and identify which jobs can be done with the measuring tool shown.

### Lengthy Journeys

##### Stage: 2 Challenge Level:

Investigate the different distances of these car journeys and find out how long they take.

### Clock Hands

##### Stage: 2 Challenge Level:

This investigation explores using different shapes as the hands of the clock. What things occur as the the hands move.

### Place Your Orders

##### Stage: 3 Challenge Level:

Can you rank these sets of quantities in order, from smallest to largest? Can you provide convincing evidence for your rankings?

### Clocking Off

##### Stage: 2, 3 and 4 Challenge Level:

I found these clocks in the Arts Centre at the University of Warwick intriguing - do they really need four clocks and what times would be ambiguous with only two or three of them?

### Clocks

##### Stage: 2 Challenge Level:

These clocks have been reflected in a mirror. What times do they say?

### Watch the Clock

##### Stage: 2 Challenge Level:

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?

### In Order

##### Stage: 2 Challenge Level:

Can you rank these quantities in order? You may need to find out extra information or perform some experiments to justify your rankings.

### Now and Then

##### Stage: 2 Challenge Level:

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.

### Eclipses of the Sun

##### Stage: 2 and 3

Mathematics has allowed us now to measure lots of things about eclipses and so calculate exactly when they will happen, where they can be seen from, and what they will look like.

### All in a Jumble

##### Stage: 3 Challenge Level:

My measurements have got all jumbled up! Swap them around and see if you can find a combination where every measurement is valid.

### You Tell the Story

##### Stage: 2 Challenge Level:

Can you create a story that would describe the movement of the man shown on these graphs? Use the interactivity to try out our ideas.