There were seventeen bales of hay in the barn and thirty bales in the shed. Mike stacked more bales in the barn today. There are now seventy-four bales of hay in the barn. How many bales did he store in the barn?

How do you find p(a and b) if a and b are independent events for two or more actions, such as tossing a coin twice and finding p(heads and heads)? 2. how do you find p(a or b) if a and b are independent events for one action, such as spinning a four-color spinner once and finding p(red or blue)?