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SashulF [63]
3 years ago
9

How do you get 25% of what number is 21

Mathematics
2 answers:
Y_Kistochka [10]3 years ago
8 0
Method 1 (works for any %)

you can use the algorithm is/of = %/100

so .. 21/x=25/100

cross multiply you get 2100=25x

now divide both sides by 25 you get 84

Method 2 (works for percents that are easy fraction like 25%, 10% etc)

you can also see that 25% is 1/4... so if 1/4 is 21 then what is 4/4?

4 times 21 is 84
<span />
Savatey [412]3 years ago
6 0
You just needed to do is 25% and then times it by 21 you should get 5.25
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Step-by-step explanation:

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The graph of a quadratic function has roots at -3 and -7 and a vertex at (-5, 4). What is the equation of the function in vertex
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Answer:

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Step-by-step explanation:

The roots are -3 and -7, so:

y = a (x + 3) (x + 7)

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3 0
3 years ago
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nikklg [1K]

Answer:

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Step-by-step explanation:

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A stack of books is 5 feet high. If the average book is three inches high, how many books are in the stack?
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Read 2 more answers
A pole that is 3.2 m tall casts a shadow that is 1.49 m long. At the same time, a nearby tower casts a shadow that is 46.75 m lo
AlekseyPX

Answer: 3.2/1.53=x/41.5

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Step-by-step explanation:

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