Example 1 Solve the following three problems.
Write the words PERCENT, WHOLE, or PART under each problem to show which piece you were solving for.
60% of 300 =
60% of
= 300 60 out of 300 =
How did your solving method differ with each problem?

What is the value of x when x + 7 = 21?

White shapes and black shapes are used in a game. some of the shapes are circles. while the rest are squares. the ratio of the number of white shapes to the number of black shapes is 5: 11. the ratio of the number of white cicrles to the number of white squares is 3: 7. the ratio of the number of black circles to the number of black squres is 3: 8. work out what fraction of all the shapes are circles.

Aclassroom is made up of 11 boys and 14 girls. the teacher has four main classroom responsibilities that she wants to hand out to four different students (one for each of the four students). if the teacher chooses 4 of the students at random, then what is the probability that the four students chosen to complete the responsibilities will be all boys?