Number Detective

Follow the clues to find the mystery number.

Six Is the Sum

What do the digits in the number fifteen add up to? How many other numbers have digits with the same total but no zeros?

ABC

In the multiplication calculation, some of the digits have been replaced by letters and others by asterisks. Can you reconstruct the original multiplication?

One Million to Seven

Age 7 to 11 Challenge Level:

Start by putting one million ($1 000 000$) into the display of your calculator.

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Can you reduce this to $7$ using just these six buttons - the $7$ key and add, subtract, multiply, divide and equals as many times as you like?

What is the shortest way can you find to do it?