It's a because 5 divided by 9 equals .555555555555556. The 6 is just from rounding the number. Otherwise the five would go on forever. The bar means go on forever. So it .5 with a bat over the 5
I think the answer is 96.
You can see that an odd number of steps is simply multiplying the number of steps by a number that moves up one each time. For instance, 1*1, 3*2, 5*3, etc. It's a bit harder with the even numbers. Their pattern is multiplying half the number of steps by 1.5, but the ones place value moves up a number each time, for example, 2*1.5, 4*2.5, 6*3.5. This means that 10 steps is 10 * 5.5, or 55 blocks and that 100 is 5,050 steps.