Answer:
0.345
Step-by-step explanation:
hits/at-bats = 345/1000 = 0.345
The probability of a hit, any particular time he goes to bat. is 0.345.
The problem does not request any particular format, so 0.345 is a perfectly good answer.
In baseball, that is called a 'batting average', and is actually expressed that way - as a decimal - in a player's statistics.
On the other hand, if we did want to express the probability as a percentage, we would do this:
0.345 * 100% = (0.345 * 100) % = 34.5 %
Hope this helps