Give the step-by-step reasoning process and then the final answer. A small pizza has 6 slices, a medium pizza has 8 slices whereas a large pizza has 12 slices. How many slices of pizza will you have if you bought a total of 15 pizzas and you know you ordered 4 small pizzas and 5 medium pizzas?
We know that 4 small pizzas and 5 medium pizzas = 4 + 5 = 9 non - large pizzas were purchased. Because a total of 15 pizzas were purchased then 15 - 9 = 6 large pizzas were ordered. If 1 small pizza has 6 slices then 4 small pizzas will have 4 * 6 = 24 slices. Similarly, If 1 medium pizza has 8 slices then 5 medium pizzas will have 5 * 8 = 40 slices. Similarly, If 1 large pizza has 12 slices then 6 large pizzas will have 6 * 12 = 72 slices. That means in total we have 24 small slices + 40 medium slices + 72 large slices = 24 + 40 + 72 = 136 slices of pizza.
The final answer: 136.