A number is chosen at random form the first 100 positive integers, what is the probability that the number is chosen is divisible by 5 or 6?.

Sanderson is having trouble with his assignment. his shown work is as follows: − 3 7 7 3 = − 3 7 × 7 3 = − 21 21 = −1 however, his answer does not match the answer that his teacher gives him. complete the description of sanderson's mistake. find the correct answer.