### Burning Down

One night two candles were lit. Can you work out how long each candle was originally?

### Percentage Unchanged

If the base of a rectangle is increased by 10% and the area is unchanged, by what percentage is the width decreased by ?

### Digit Sum

What is the sum of all the digits in all the integers from one to one million?

# Megabytes and Kilobytes

##### Age 14 to 16 ShortChallenge Level

$1$ kilobyte is actually not $1000$ bytes, it is $2^{10}$ bytes.

$1$ megabyte is $2^{10}$ kilobytes.

How many bytes are there in $1$ megabyte?

This problem is adapted from the World Mathematics Championships
You can find more short problems, arranged by curriculum topic, in our short problems collection.