Given the following proportion:

You can follow the steps shown below in order to solve for "s" and find its value:
1. You can apply the Multiplication property of equality by multiplying both sides of the equation by "s":

2. Apply the Multiplication property of equality again by multiplying both sides of the equation by 21:

3. Finally, you must apply the Division property of equality by dividing both sides of the equation by 36:

The answer is:
