To find Steven's batting average, we need to divide the number of times he got on base (15) by the total number of at-bats (45):
15/45
We can simplify this fraction by dividing both the numerator and denominator by 15:
15/45 = (15 ÷ 15) / (45 ÷ 15) = 1/3
Therefore, Steven's batting average is 1/3, which is equivalent to 0.333 as a decimal.