Students in the Class
Number Concepts: Fractions and Decimals
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.
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.
approximately 20 minutes
Resources & Materials
Pencil and paper, computer, NuCalc, Excel
NCTM Process Standards
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
Link's) to lesson plan and other materials
Link to Students in Class Spreadsheet