Consider the question. Elijah is painting his living room and decides to buy masking tape to make his painting neater. 2 of his walls are 4 meters wide and the other 2 walls are 6 meters wide. Elijah needs enough masking tape to cover the entire width of each wall and can order the exact amount of masking tape he needs. How many meters of masking tape does Elijah need to order?
 What is the step-by-step reasoning process to arrive at the answer: 20?
For 2 of the walls, Elijah will need 2 walls * 6 meters each = 12 meters of masking tape. For the other 2 walls, he will need 2 walls * 4 meters each = 8 meters of masking tape. He will therefore need a total of 12 + 8 = 20 meters of masking tape.