What is the sum of the first 100 positive multiples of 4?

To find the sum of the first 100 positive multiples of 4, we can use the formula for the sum of an arithmetic series: Sn = n/2 * (a1 + an), where Sn is the sum, n is the number of terms, a1 is the first term, and an is the last term. In this case, a1 = 4, an = 4*100 = 400, and n = 100. Plugging these values into the formula, we get: Sn = 100/2 * (4 + 400) = 50 * 404 = 20,200. Therefore, the sum of the first 100 positive multiples of 4 is 20,200.