1. Total even numbersSequence: 100, 102, ..., 998This is an A.P. with a=100,d=2, last term 998 .n=2998−100​+1=2898​+1=449+1=450.So, 450 even numbers.2. Even numbers divisible by 3→ multiples of 6Between 100 and 998:- First multiple of 6≥100 is 102(6×17)- Last multiple of 6≤998 is 996(6×166)Count:166−17+1=1503. Even numbers divisible by 5→ multiples of 10Between 100 and 998:- First: 100=10×10- Last: 990=10×99Count:99−10+1=90 4. Even numbers divisible by both 3 and 5→ multiples of 30Between 100 and 998:- First: 120=30×4- Last: 990=30×33Count:33−4+1=305. Use inclusion-exclusion on even numbersEven numbers divisible by 3 or 5 :150+90−30=210.6. Not divisible by 3 or 5450−210=240.