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Puzzles to test mathematical skills, set by Anita Straker. Solutions below More brainteasers on

Digit sums

1. I am a number on a 100-square.

The sum of my digits is 10.

If you reverse my digits the resulting number is 18 less than I am.

Which number am I?

2. I am a number on a 100-square.

I am 20 less than nine times the sum of my digits.

My tens digit is one more than my units digit. Which number am I?

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