GED Math : Complex Operations
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Example Questions
Example Question #37 : Proportions And Percentages
Gerald's current monthly rent is $720. His rent will increase by 20% starting in January; it will increase by $50 starting in July. How much rent will Gerald pay from January to December?
If Gerald's current rent is $720, then a 20% increase in rent will be an increase of
This makes Gerald's rent from January to June
His rent from July to December will be $50 more than this, or
Over the next year, Gerald will pay $864 in monthly rent for six months, then $914 in monthly rent for six months. This is
in rent total.
Example Question #31 : Proportions And Percentages
Quinn invests $6,000 in stocks and bonds. He invests 60% of the money in corporate bonds which, over the next year, return 8%. The remainder, he invests in a preferred stock, which ends up producing a loss of 4%. How much money has Quinn gained or lost from his investments?
Quinn has lost $384
Quinn has gained $384
Quinn has gained $192
Quinn has lost $192
Quinn has gained $192
60% of 6,000 is 
Quinn invests 
Quinn has a net gain of
from his investments.
Example Question #39 : Proportions And Percentages
Seven tenths of three fourths of 
Seven tenths of three fourths of 
Example Question #71 : Complex Operations
What is 40% of 80% of 
80% of 
40% of this is 
Example Question #41 : Proportions And Percentages
Ten percent of a number is six more than 5 percent of this number. Find the number.
The key word "is" indicates equality.
Ten percent of a number:
Six more than 5 percent of this number:
Solve and simplify:
Example Question #71 : Complex Operations
45% of what number is 9?
The rate is 45% and the comparative number is 9; the unknown is the original number that 9 is 45% of. The statement is "(nine) is (forty-five percent) of (some number)", so the variable stands for a number.
Example Question #41 : Proportions And Percentages
A building that is 
To solve this you would set up and solve a direct proportion:
Example Question #44 : Proportions And Percentages
Bob's Bargain Basement has computer tables on sale at 50% off the retail price. For the holiday, an additional 15% is deducted. If the computer table is $240, how much is the table on sale for during the holiday?
In order to calculate the amount of the purchase, you first must find the cost of the table at 50% off. This can be done by taking 
This could also be done by converting the percent to a decimal and then multiplying that decimal by the original cost.
Then, the next step would be to take 15% of the $120. This is done by converting the percent to a decimal and then multiplying by $120.
15% = .15 as a decimal
This additional savings of $18.00 would then be subtracted from the $120.00.
This is the amount that will be paid after all discounts and savings.
Note: Do not add the initial savings of 50% to the additional savings of 15% to get a total savings of 65% and then work your problem from there. That is not the correct way to work this problem!
Example Question #45 : Proportions And Percentages
Solve:
Cross multiply the terms.
Divide by eight on both sides.
The answer is:
Example Question #46 : Proportions And Percentages
What is 30% of 750?
To find a percentage of a whole number, we will multiply the percentage by the whole number. So, we get
To make things easier, we will simply by cancelling out the zeros. So, we get
Therefore, 30% of 750 is 225.
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