Proportion in Word Problems
Word or story problems give us a first glimpse into how mathematics is used in the real word. To be solved, a word problem must be translated into the language of mathematics, where we use symbols for numbers - known or unknown, and for mathematical operations. Here we continue the tutorial started earlier.
The problem we are going to discuss (and solve) includes a proportion which is an equality of two ratios, i.e., a relation between four quantities. Three will be specified in the problem, whereas the value of the fourth will be unknown at the outset and eventually found as the result of out problem solving activity.
We may or may not reduce the problem to that of class a·x = b.
(Note: In the applet below, all underlied words and numbers can be clicked on. Please feel free to do just that.)
Note there is a way (that actually uses proportions) of soving the problem without first finding the cost of a single candy (bar, etc.).
(There are many more word problems discussed and solved at this site. The math tutorial continues with a similar approach over several additional examples.)
- Problems of class a + x = b
- Problems of class a · x = b
- From Word Problem to Equation
- Problems of class x / a = b / c
- Problems of class x = a + b
- Problems of class x = a + b (II)
- Problems of class x = a × b
- Solving Two Simultaneous Linear Equations
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