Present two concrete examples from the world around you, one that illustrates the application of proportional quantities and the other as a percentage

There are 20 children in the cast of a class play and 8 of the children are boys of the boys 4 have a speaking part in the play and of the girls 8 do not have a speaking part in the play if a child from the cast of the place chosen at random what is the probability that the child has a speaking part

Write the rational number in lowest terms 99/-15

How is working backward similar to solving an equation?