One approach we can take is to determine how many teaspoons are needed to make 1 serving. If 1/4 tsp makes 16 servings, then we can divide 1/4 by 16 to figure out how many tsp make 1 serving.
1/4 ÷ 16 = 1/4 * 1/16 = 1/64 tsp
It takes 1/64 tsp to make 1 serving, so to determine how many tsp make 35 servings, multiply 1/64 * 35
Can you take it from there, Carisa?
