# If you are only allowed to press the 1 and 0 keys on a calculator with + - / x =, how many min press required to get 9?

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If you are only allowed to press the 1 and 0 keys on a calculator with any of the add, take, times, divide and equals keys, what is the fewest number of presses needed to make the number 9 on the calculator?

posted May 16

## 1 Solution

+1 vote

I think we need 5 key strokes to do this.
1, 0, -, 1 & =

solution May 16
How only 5 keys strokes required?
10-1=

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