Lisa got 14 out of 30 questions correct on her quiz. What is this as a percent?
4 Answers
Explanation:
Multiply the numerator and denominator by
Or just use a calculator to divide.
But as this is a test results, it would probably be given as 47% by rounding to the nearest whole number.
Explanation:
Fractions, decimals and percentages are all different way of expressing the same relationship between two numbers. They are interchangeable.
Just dividing will give 0.466666666...
But the first 2 decimal places represent hundredths which indicate percent.
So this value could also be written as
From this we see that it is 46.6666 %
However, recurring decimals in percentages (especially thirds and sixths) are better written in fraction form.
So the best way of giving an exact answer without rounding off is as
Or multiply by 100% (100% = 1,) so we are not changing the value.
=
However as this is for a test, a whole number answer would probably be given as 47%
Explanation:
To construct a percentage we require to form a fraction and multiply it by 100.
The required fraction is found as follows.
#color(red)("number of correct questions")/color(blue)("total number of questions")#
#rArrcolor(red)("14")/color(blue)("30")# To obtain this fraction as a percentage, multiply by 100.%
#rArr14/30xx100/1# which may be simplified by 'cancelling' the 30 and 100 (dividing both by 10)
Thus
#(14)/(cancel(30)^3) xxcancel(100)^(10)/1 %=(14xx10)/(3xx1)=140/3 %# and
#140/3%=46 2/ 3%=46.66...=46.6bar6%#
There are two ways of writing percentage. Suppose we are talking about 25 percent.
The most common way of seeing this is in the format of
For the purpose of calculations it is convenient to write
The word percent can be split into 2 parts
Part 1: 'per' means for each of.
Part 2: 'cent' means 100. Think of centenary,
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Using the principle of the fraction format.
Let the unknown count be
14 out of 30
Write this as a ratio
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From here we have two options of approach.
Method 1: ( shortcut approach) Multiply both sides by 100 so that you find the value of
Method 2: Treat as a ratio and proportion up so that the denominator of
The shortcut method really is the same as method 2 but it cuts out some steps
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So
To write
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For multiply or divide, what we do to the bottom we do to the top!
As a percentage we write it as