For the first deployments of B-29's into China and India for attacks on Japan, the B-29's flew very high (27-32k), were not able to hit the targets with bombs, and suffered more casualties to mechanical failures of the B-29 than to enemy aircraft.
There were some missions, though, where the Japanese launched 100 fighters to intercept 100 or so B-29's where some B-29's were shot down.
After these early days of B-29 use, the B-29's moved to Pacific islands, flew in increasing numbers, and the ratio of Japanese fighters to B-29's decreased greatly. They still used high-altitude bombing, and still mostly missed targets, so they moved from trying to hit industrial and military targets to use of incindiaries and area bombing of cities.
After that, LeMay tried a gamble/test of B-29's at 9k at night. That's as far into the book as I am at the moment regarding B-29 missions.
Now I'm in the part about the first carrier-based aircraft attacks on Japan. (The first CV attacks are definitely good for special events, as many of those fights were fairly even in numbers with the Japanese pilots having late-war aircraft.)