Problem Solving (PS) | Re: Of the three-digit integers greater than 800

Total number of 3 digit numbers = 199
Total number of 3 digit numbers with all digits same = 2
Total number of digits will all digits different greater than 800 = 9 * 8= 72
Total number of digits will all digits different greater than 900 = 9*8 =72
199 -(2+72*2)=53_

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