Saxon Course 2: Lesson 22 (Slides)

Lesson 22

• Problems About a Fraction of a Group

​Using a Diagram

• Example:

  Diagram this statement. Then answer the questions that follow.

  Two fifths of the 30 students in the class are boys.

  a. How many boys are in the class?

  b. How many girls are in the class?

• Solution:

  We draw a rectangle to represent all 30 students. Since the statement uses fifths to describe a part of the class, we divide the diagram into 5 parts. Since 30/5 = 6, there are 6 students in each part!

​a. 12 boys
b. 18 girls

​Shortcut

• We can find 2/5s of 30 without using a diagram in two steps!

​2

​5

​of 30

​step 1: Divide the whole number by the denominator (5)

​30 divided by 5 = 6

​step 2: Multiply by the numerator (2)

​6 times 2 = 12

​= 12

​Daily Challenge #22
Draw a diagram!
Three fourths of the 60 marbles in the bag were red.
A. How many marbles were red?
B. How many marbles were not red?

​Still confused?