Solve this number riddle: i am an odd number. i am less than 100.the sum of my digits is 12.i am a multiple of 15. what number am i

The answer is 3 because it is a multiple of 12 and 15 and is less than 100 and is odd

First step is to get rid of the square root. remember that a square root is the same as raising to the (1/2) power. see below: multiply exponents per exponent rules to get: remember you subtract exponents from the denominator and add exponents in the numerator so: simplify further: so a is the correct choice. if you don't understand this google exponent rules and it will you understand. look at the image results.