PERCENT PROBLEMS
There are basically three types of percent problems. So lets explain that by making up a simple percent problem. 50% 80 = 40 This means that 80 is multiplied by 50% and your answer is 40.
To solve any percent problem you must have two out of the three bits of information in the above example. The three types of percent problems differ only in regard to what information is not given to you. The three types are:
1) 50% t = 40 t represents the original amount 80
2) t% 80 = 40 t represents the % 40 is of 80
3) 50% 80 = t t represents the amount that is 50% of 80
In all three of the above example you have two out of the three bits of information from the original problem 50% 80 = 40.
In order to understand how to solve the above three examples let us look at a simple multiplication problem from elementary school.
3 x 4 = 12 To prove that the answer 12 is correct we can divide 12 by 3 or 12 by 4 and get the other number. for instance 12 ÷ 3 = 4 and 12 ÷ 4 = 3
Remember anytime two numbers are multiplied together and we get an answer the answer divided by either number must give you the other number as it does in the 3 x 4 =12 problem.
In the problem 50% 80 = 40; 80, 50% are numbers that are multiplied together. 40 is the answer from the multiplication. Hence in examples 1 and 2 and according to the 3 x 4 = 12 example if we divide the answer 40 by one of the numbers we are multiplying together, we must get the other number:
1) 50% t = 40 t = 40 ÷ 50% → 40 ÷.50 = 80
2) t% 80 = 40 t% = 40 ÷ 80 → 40 ÷ 80 = .5 which = 50% t = 50%
The third type of percent problem is straight multiplication:
3) 50% 80 is a multiplication problem of .50 x 80 = t → 40 = t