Math Problem : GG.7 Divide three numbers by the same number

I divided 75,121 and 190 by the same divisor and I had the same remainder of each division.

Find the divisor.




Answer
23

Solution
The number obtained by subtracting the remainder from three numbers can be divided by the same number. 

That means that 190 - 121 = 69 which is the difference of 121 and 190 and 121 - 75 = 46 which is the difference of 75 and 121 should be also divisible by the same number. 

The common measure of 69 and 46 are 1 and 23 then we can find the divisor was 23.