Elbert wants to plant grass seed in his backyard. His yard is shaped like a rectangle that is 6 meters by 7 meters. He plans to use a cup of seed for every square meter in his yard. How many cups of grass seed will he need?

A = LW

A = 6 * 7
A = 42 sq. meters

To find out how many cups of grass seed Elbert will need, you need to calculate the area of his backyard and then multiply it by the number of cups of seed per square meter.

Step 1: Calculate the area of the backyard.
Elbert's backyard is shaped like a rectangle with dimensions of 6 meters by 7 meters. The formula to calculate the area of a rectangle is length × width. Therefore, the area of Elbert's backyard is 6 meters × 7 meters = 42 square meters.

Step 2: Determine the number of cups of seed per square meter.
The problem states that Elbert plans to use a cup of seed for every square meter in his yard. Therefore, he needs 1 cup of seed per 1 square meter.

Step 3: Calculate the total number of cups of grass seed needed.
Multiply the area of the backyard by the number of cups of seed per square meter:
42 square meters × 1 cup of seed per 1 square meter = 42 cups of grass seed.

So, Elbert will need 42 cups of grass seed to cover his backyard.