What is the answer of this question?

One astronomical unit (1 au) is about 1.496 alt tag missing. kilometers. if you wrote this number of kilometers in regular decimal notation (for example, 528 and 3,459 are written in regular decimal notation), how many zeros would your number have?

The quotient of 15 and a number is 1 over 3 written as an equation

Find the value of x. also give me an explanation so i can complete it to other questions as well, : )