Intermath | Workshop Support
Lesson Plan Number Four

Students in the Class

Number Concepts:  Fractions and Decimals

Grade levels
Sixth and Seventh

The problem stated:  Five-eighths of the students in a class are boys. After six girls join the class, the number of boys and girls in the class is the same. How many students are in the class now?

We first approached the problem using basic algebra.  Mike and I came up with the equation 3/8x + 6 = 5/8x.  The solution to this problem was 24.  We then decided to explore other options.  We first tried NuCalc and found that not workable. We then went to Excel and made a spreadsheet using the formula:  .375*a2+6-.635*a2.  When the value became 0 we found the solution that met the one we used.  

Lesson Type 

We started out with pencil and paper and then went to computer.  This lesson could also be done with hands on using  a balance scale.

Estimated time
approximately 20 minutes

Resources & Materials
Pencil and paper, computer, NuCalc, Excel

NCTM Process Standards
     Standard 5: 
          1.  understand, represent, and use numbers in a variety of equivalent forms in real-world and mathematical problem situations
          2.  develop number sense for whole numbers, fractions, decimals, integers, and rational numbers

Name and contact information
Peggy Reigle

Link's) to lesson plan and other materials
Link to Students in Class Spreadsheet