# Question: 21 is 30 percent of what number

## Step by step solution for calculating 21 is 30 percent of what number

We already have our first value 21 and the second value 30. Let's assume the unknown value is Y which answer we will find out.

As we have all the required values we need, Now we can put them in a simple mathematical formula as below:

STEP 1 21 = 30% × Y

STEP 2 21 = 30/100× Y

Multiplying both sides by 100 and dividing both sides of the equation by 30 we will arrive at:

STEP 3 Y = 21 × 100/30

STEP 4 Y = 21 × 100 ÷ 30

STEP 5 Y = 70

Finally, we have found the value of Y which is 70 and that is our answer.

You can easily calculate 21 is 30 percent of what number by using any regular calculator, simply enter 21 × 100 ÷ 30 and you will get your answer which is 70

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Here is a Percentage Calculator to solve similar calculations such as 21 is 30 percent of what number. You can solve this type of calculation with your values by entering them into the calculator's fields, and click 'Calculate' to get the result and explanation.

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## Sample questions, answers, and how to

Question: Your friend has a bag of marbles, and he tells you that 30 percent of the marbles are red. If there are 21 red marbles. How many marbles does he have altogether?

How To: In this problem, we know that the Percent is 30, and we are also told that the Part of the marbles is red, so we know that the Part is 21.

So, that means that it must be the Total that's missing. Here is the way to figure out what the Total is:

Part/Total = Percent/100

By using a simple algebra we can re-arrange our Percent equation like this:

Part × 100/Percent = Total

If we take the "Part" and multiply it by 100, and then we divide that by the "Percent", we will get the "Total".

Let's try it out on our problem about the marbles, that's very simple and it's just two steps! We know that the "Part" (red marbles) is 21.

So step one is to just multiply that Part by 100.

21 × 100 = 2100

In step two, we take that 2100 and divide it by the "Percent", which we are told is 30.

So, 2100 divided by 30 = 70

And that means that the total number of marbles is 70.

Question: A high school marching band has 21 flute players, If 30 percent of the band members play the flute, then how many members are in the band?

Answer: There are 70 members in the band.

How To: The smaller "Part" in this problem is 21 since there are 21 flute players and we are told that they make up 30 percent of the band, so the "Percent" is 30.

Again, it's the "Total" that's missing here, and to find it, we just need to follow our 2 step procedure as the previous problem.

For step one, we multiply the "Part" by 100.

21 × 100 = 2100

For step two, we divide that 2100 by the "Percent", which is 30.

2100 divided by 30 equals 70

That means that the total number of band members is 70.

## Have time and want to learn the calculation?

Let's assume the unknown value is Y

First writing it as: 100% / Y = 30% / 21

Drop the percentage marks to simplify your calculations: 100 / Y = 30 / 21

Multiply both sides by Y to move Y on the right side of the equation: 100 = ( 30 / 21 ) Y

Simplifying the right side, we get: 100 = 30 Y

Dividing both sides of the equation by 30, we will arrive at 70 = Y

This leaves us with our final answer: 21 is 30 percent of 70

## Percentage Table

 21 is 30 percent of 70 21.01 is 30 percent of 70.033 21.02 is 30 percent of 70.067 21.03 is 30 percent of 70.1 21.04 is 30 percent of 70.133 21.05 is 30 percent of 70.167 21.06 is 30 percent of 70.2 21.07 is 30 percent of 70.233 21.08 is 30 percent of 70.267 21.09 is 30 percent of 70.3 21.1 is 30 percent of 70.333 21.11 is 30 percent of 70.367 21.12 is 30 percent of 70.4 21.13 is 30 percent of 70.433 21.14 is 30 percent of 70.467 21.15 is 30 percent of 70.5 21.16 is 30 percent of 70.533 21.17 is 30 percent of 70.567 21.18 is 30 percent of 70.6 21.19 is 30 percent of 70.633
 21.2 is 30 percent of 70.667 21.21 is 30 percent of 70.7 21.22 is 30 percent of 70.733 21.23 is 30 percent of 70.767 21.24 is 30 percent of 70.8 21.25 is 30 percent of 70.833 21.26 is 30 percent of 70.867 21.27 is 30 percent of 70.9 21.28 is 30 percent of 70.933 21.29 is 30 percent of 70.967 21.3 is 30 percent of 71 21.31 is 30 percent of 71.033 21.32 is 30 percent of 71.067 21.33 is 30 percent of 71.1 21.34 is 30 percent of 71.133 21.35 is 30 percent of 71.167 21.36 is 30 percent of 71.2 21.37 is 30 percent of 71.233 21.38 is 30 percent of 71.267 21.39 is 30 percent of 71.3
 21.4 is 30 percent of 71.333 21.41 is 30 percent of 71.367 21.42 is 30 percent of 71.4 21.43 is 30 percent of 71.433 21.44 is 30 percent of 71.467 21.45 is 30 percent of 71.5 21.46 is 30 percent of 71.533 21.47 is 30 percent of 71.567 21.48 is 30 percent of 71.6 21.49 is 30 percent of 71.633 21.5 is 30 percent of 71.667 21.51 is 30 percent of 71.7 21.52 is 30 percent of 71.733 21.53 is 30 percent of 71.767 21.54 is 30 percent of 71.8 21.55 is 30 percent of 71.833 21.56 is 30 percent of 71.867 21.57 is 30 percent of 71.9 21.58 is 30 percent of 71.933 21.59 is 30 percent of 71.967
 21.6 is 30 percent of 72 21.61 is 30 percent of 72.033 21.62 is 30 percent of 72.067 21.63 is 30 percent of 72.1 21.64 is 30 percent of 72.133 21.65 is 30 percent of 72.167 21.66 is 30 percent of 72.2 21.67 is 30 percent of 72.233 21.68 is 30 percent of 72.267 21.69 is 30 percent of 72.3 21.7 is 30 percent of 72.333 21.71 is 30 percent of 72.367 21.72 is 30 percent of 72.4 21.73 is 30 percent of 72.433 21.74 is 30 percent of 72.467 21.75 is 30 percent of 72.5 21.76 is 30 percent of 72.533 21.77 is 30 percent of 72.567 21.78 is 30 percent of 72.6 21.79 is 30 percent of 72.633
 21.8 is 30 percent of 72.667 21.81 is 30 percent of 72.7 21.82 is 30 percent of 72.733 21.83 is 30 percent of 72.767 21.84 is 30 percent of 72.8 21.85 is 30 percent of 72.833 21.86 is 30 percent of 72.867 21.87 is 30 percent of 72.9 21.88 is 30 percent of 72.933 21.89 is 30 percent of 72.967 21.9 is 30 percent of 73 21.91 is 30 percent of 73.033 21.92 is 30 percent of 73.067 21.93 is 30 percent of 73.1 21.94 is 30 percent of 73.133 21.95 is 30 percent of 73.167 21.96 is 30 percent of 73.2 21.97 is 30 percent of 73.233 21.98 is 30 percent of 73.267 21.99 is 30 percent of 73.3