my approach is

from 60 to 1999 is 1399 but add 1 since inclusive

both 5 AND 13 are prime number so anumber to be divisible by both 13 and 5 must be a multiple of both 5 and 13 HENCE 65

SO I found the number of multiple of 65 in the 14OO numbers

14OO/ 65 = 21 of such number

HENCE final result is 21/1400

By the way i don 't understand why some of you are doing the following :

65*10=650 (lowest common multiple)

65*30=1950 (highest common multiple)

30-10=21 (inclusive)

thanks

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