To lift an 110 pound (50 KG) person, you’ll need 3571 helium balloons.
If you weigh 50 kilograms (about 110 pounds), then you weigh 50,000 grams. Divide your 50,000 grams by the 14 grams per balloon and you find that you need 3,571.42 balloons to lift your weight. You might want to add 500 more if you actually would like to rise at a reasonable rate.