Algebra 1 : How to find the part from the whole with percentage

Study concepts, example questions & explanations for Algebra 1

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Example Questions

Example Question #1 : How To Find The Part From The Whole With Percentage

What number is 25% of 80? 

Possible Answers:

25

24

20

40

75

Correct answer:

20

Explanation:

To solve this problem, we set up a proportion. We are looking for the number which is 25% of 80, thus we set up 25/100 = x/80. We set up this proportion so that the "wholes" are on the same side of the fraction. Then we simplify the left side (since 25/100 = 1/4) to make our arithmetic a bit easier. We now have 1/4 = x/80. Cross multiplying, we get 80 = 4x. Dividing both sides by 4, we get x = 20.

25% = 25/100

Example Question #2 : How To Find The Part From The Whole With Percentage

14% of 50 is _____?

Possible Answers:

Correct answer:

Explanation:

Divide numerator and denominator by 2 and you get , so 7 is 14% of 50.

Example Question #3 : How To Find The Part From The Whole With Percentage

Julie made 500 handbags last year.  She gave 15 away and sold 185.  What percentage of the 500 handbags crafted does she still have in her inventory?

Possible Answers:

Correct answer:

Explanation:

Example Question #4 : How To Find The Part From The Whole With Percentage

What is 35% of 200?

Possible Answers:

Correct answer:

Explanation:

To find 35% of 200, we just need to multiply

 

This gives us our answer, 70. Alternatively, we could realize instinctively that 35% of 100 is 35, and then double it to get the same answer.

Example Question #5 : How To Find The Part From The Whole With Percentage

What is 64% of 86?

Possible Answers:

Correct answer:

Explanation:

First, write 64% as a decimal. Just move the decimal point of 64% two digits to the left and then eliminate the % so that we get 0.64.  Thus, 64%=0.64. Then multiply that 0.64 by 86

So 55 is 64% of 86.

Example Question #5 : How To Find The Part From The Whole With Percentage

Wendy and Bob are cleaning their house at the same speed. Working together, they can clean the house in 8 hours. What percentage of the house can Wendy clean in 4 hours if she is cleaning by herself?

Possible Answers:

Correct answer:

Explanation:

It takes Bob and Wendy 8 hours to clean the entire house, for a total of 16 man-hours. This means that one hour of cleaning by one person will clean of the house, or 6.25%. Thus, Wendy can clean 25% of the house by herself in 4 hours.

Example Question #7 : How To Find The Part From The Whole With Percentage

What is  of , rounded to the nearest tenth? 

Possible Answers:

Correct answer:

Explanation:

Convert 34% to a decimal: 0.34

Multiply 0.34 by 492: 167.28

Round to the nearest tenth: 167.3

Example Question #8 : How To Find The Part From The Whole With Percentage

Choose the correct answer. 

What is  of 

Possible Answers:

Correct answer:

Explanation:

To find a part of the whole number, you multiply the percentage in decimal form against the whole number. The first step is to convert the percentage into a decimal,  to . Then multiply the decimal against the whole number,  

Example Question #7 : How To Find The Part From The Whole With Percentage

Select the correct answer. 

What is  of 

Possible Answers:

Correct answer:

Explanation:

To find the part of the whole, first convert the percentage to a decimal,  to , then multiply the decimal against the whole number given, , resulting in . Alternatively, we know that  is equal to  , so we could divide the whole number, ,  into four equal parts, which would be . Since we need   (three quarters), we multiply  , resulting in 

Example Question #8 : How To Find The Part From The Whole With Percentage

If  of the student body is female, what is the percentage of males? 

Possible Answers:

Correct answer:

Explanation:

If  of the student body is female, this is equivalent to .  Since  is the whole, . Thus  is not female.

Alternatively, if  is not male, then the rest must be male, so  . Then we can convert that decimal to a percentage, 

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