Canh đồng hồ
- Thời gian
- Ages 8 to 13
- About 6 minutes
The story behind it
Until the 1880s a player could think for as long as he liked, and some games lasted most of a day. Then came a clock with two faces: press your button and your time stops while your opponent’s runs. Chess has been a sum in minutes and seconds ever since.
Read the full story: The clock with two faces →How to play
- Read the clock and the question.
- One minute is sixty seconds.
- Work it out, then choose.
Levels
For teachers and coaches
Clock watch — Time
Ages 8 to 13 · about 6 minutes · 8by8verse Chess Lab
What it teaches
Converting minutes and seconds, subtracting times, and multiplying a rate.
The story to tell first
Until the 1880s a player could think for as long as he liked, and some games lasted most of a day. Then came a clock with two faces: press your button and your time stops while your opponent’s runs. Chess has been a sum in minutes and seconds ever since.
Three questions to ask
- Why do we change minutes into seconds before dividing?
- You get three extra seconds every move. After twenty moves, how much is that?
- Is it wiser to spend your time evenly, or to save it for the hard moves?
Without a screen
Time a pupil doing ten sums. Work out seconds per sum, then predict the time for twenty-five.
Tiếp
Finish
Hint
Step back
Start again
Play again
Next level
Back to the lab
Right.
Not quite.
Not yet — have another go.
Question {n} of {total}
{right} out of {total} right.
Three stars. Clean work.
Two stars. Well played.
One star. Level done.
king
queen
rook
bishop
knight
pawn
{n} seconds
You have {m} minutes for {n} moves. If you spend the same time on each, how long is one move?
{m} minutes is {s} seconds. Shared by {n} moves, that is {p} seconds each.
You started with {m} minutes and have used {u}. What does your clock show?
{m} minutes take away {u} leaves {l}.
You start with {m} minutes and gain {i} seconds after every move. After {n} moves you have spent {u} thinking. What does your clock show?
After thinking you would have {a}. The bonus adds {b} seconds: {l}.