Find out what number $350 is 8% of, since he makes 8% commission on sales. In the percent formula: a = pb
a is the part, p is the percent (as a decimal), b is the base
350 is 8% of what number? 350 = 0.08b {substituted given values into percent formula and changed 8% to a decimal}
b = $4,375 {divided each side by 0.08}
He needs to make at least $4375 worth of sales.