Math CentralQuandaries & Queries


Question from Laudacir

Four multiples of 10 are added together.the total is a 3 digit number with three consecutive digits. What could the four number be?

Hi Laudacir,

I am confused by this question. Any multiple of 10 has zero as its units digit so the sum of four multiples of 10 will also have zero as its unit digit. The only three consecutive digits that contain zero are 0, 1 and 2. Since the sum you have must be expressed as a three digit number with zero as the units digit and the three digits are 0, 1 and 2. Hence the sum must be 120 or 210. Can you find four multiples of 10 with a sum of 120? Can you find four multiples of 10 with a sum of 210?

Does this make sense?

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