One way to figure out what number is a percentage of a larger number is to convert the percent into a decimal and multiply it by the whole number. Since $\displaystyle 60\%$ is equal to $\displaystyle 0.60$, multiply this by $\displaystyle 90$.

$\displaystyle 90 \times 0.60=54$

$\displaystyle 54$ is your answer.

Rewrite $\displaystyle 125\%$ as a decimal by writing $\displaystyle 125$ with a decimal point, then shifting it two spaces left:

$\displaystyle 125.0\% = 1.25$

Multiply this by $\displaystyle 125$:

$\displaystyle 125 \times 1.25 = 156.25$

Larry bought the remaining stock which was $\displaystyle 10$% $\displaystyle 100-90=10$.  Then was given $\displaystyle 5$% by three different individuals $\displaystyle (5*3=15)$.  Larry then owned $\displaystyle 25$% $\displaystyle (10+15=25)$ not $\displaystyle 30$%

In order to convert numbers to a percent, it is easiest to set up a ratio. 

We know that percent is just per-cent or per-100, another way to write this is to divide the number by 100. 

We would set up the ratio below with x being the number we are looking for: 

$\displaystyle \frac{x}{100}=\frac{12}{25}$

Now we cross multiply 25 times x and 12 times 100 to get: 

$\displaystyle 25x=1200$

Dividing both sides by 25 will give us the percent. 

$\displaystyle \frac{25x}{25}=\frac{1200}{25}$

On the left side the 25's will cancel to give us x, on the right side we may need to do some long division to eventually find that 1200/25 = 48.

The circle is divided into 16 portions; 75% of this is

$\displaystyle 16 \times 75 \% = 16\times 0.75= 12$ squares.

5 portions are already shaded in, so it is necessary to shade in

$\displaystyle 12- 5 = 7$ more portions.

The rectangle is divided into 20 squares; 60% of this is

$\displaystyle 20 \times 60 \% = 20 \times 0.60 = 12$ squares.

7 squares are already shaded in, so it is necessary to shade in

$\displaystyle 12 - 7 = 5$ more squares.

To find a percentage of a whole number, we will multiply the percentage by the whole number.  So, we get

$\displaystyle 63\% \cdot 300$

$\displaystyle \frac{63}{100} \cdot 300$

$\displaystyle \frac{63}{100} \cdot \frac{300}{1}$

Now, the zeros can cancel out.  So, we get

$\displaystyle \frac{63}{1} \cdot \frac{3}{1}$

$\displaystyle \frac{63 \cdot 3}{1 \cdot 1}$

$\displaystyle \frac{189}{1}$

$\displaystyle 189$

Therefore, 63% of 300 is 189.

First, we need to determine the percentage of cats that are grey. To do this, we subtract $\displaystyle 100\%-32\%=68\%$. Therefore, 68% of cats are grey.

The quick estimation method allows us to compute this problem quickly and save time on later questions. To begin, we need to determine 10% of the total amount of cats. In order to find 10% of a number, simply move the decimal point one place to the left. So, 10% of 300 cats is 30 cats. 

We want to determine how many cats constitute 68% of the total amount of cats. 68% can be rounded to 70% in order to estimate and find the closest answer choice. 70% is 7 times 10% so all we need to do is multiply 10% (30 cats) by 7. Therefore,

$\displaystyle 7\cdot30\textsl{ cats}=210\textsl{ cats}$ are orange. 

Now, look at the answer choices and choose the one closest to your estimation. Keep in mind that we over estimated, so the answer you choose should be slightly less.

One way to solve this problem is to use cross multiplication. $\displaystyle 68 \% = \frac{68}{100}$

So in order to determine the number of green birds, set this proportion equal to$\displaystyle \frac{x}{1000}$.

Therefore, $\displaystyle \frac{68}{100}= \frac{x}{1000}$

Cross multiply to get $\displaystyle 100x=68\cdot1000$

$\displaystyle 100x=68000$. Now divide both sides of the equation by 100 to get

$\displaystyle x=680$ 

A faster way to solve this problem is to recognize that 100 and 1000 differ by only one decimal place (1000 has an extra zero). Therefore, in order to determine 68% of 1000, simply add an extra zero to 68 and you have 680 birds. 

First, we need to determine the percentage of snacks that are unhealthy. To do this, we subtract 

$\displaystyle 100\%-70\%=30\%$ Therefore, 30% of snacks are unhealthy.

The quick estimation method allows us to compute this problem quickly and save time on later questions. To begin, we need to determine 10% of the total amount of snacks. In order to find 10% of a number, simply move the decimal point one place to the left. So, 10% of 500 snacks is 50 snacks.

We want to determine how many snacks constitute 30% of the total amount of snacks. 30% is 3 times 10% so all we need to do is multiply 10% (50 snacks) by 3. Therefore,

$\displaystyle 3\cdot50 \textsl{ snacks}=150 \textsl{ snacks}$ are unhealthy.