Percentage Questions

Given that to find 15 of 80

=> What % of 80 is 15

Let it be 'p'

=> p% of 80 = 15

=> $$\begin{gathered} p x 80100 = 15 \\ ⇒p = 15 x 10080 \\ ⇒p = 150080 = 18.75 \end{gathered}$$

Therefore, 15 is 18.75% of 80 => 18.75% of 80 = 15

Example::

Now, in the similar way we can find 15% of 80 =?

=> 15x80/100 = p

=> p = 4 x 3 = 12

Therefore, 15% of 80 = 12

Let number of boys = B

Number of girls = G

From the given data,

1B/3 + 1G/2 = 300

But given B/3 = 100

=> B = 300

G/2 = 300 - 100

G = 200 x 2

=> G = 400

Therefore, total number of students in the college = B + G = 700.

Let the cost price of the article be 'P'

Then from given data,

$$\begin{gathered} P + 28P100 = 4544 \\ => 128P = 454400 \\ => P = 3550 \end{gathered}$$

Hence, the cost price of the article = P = Rs. 3550

Number of runs made by running = 180 - (11 x 4 + 8 x 6)
= 180 - (92)
= 88
Now, we need to calculate 88 is what percent of 180.
⇒88180×100  = 48.888%.

As per given data, P = 415600, R1= 25% incresed, R2 = 30% decreased

Population of the city at the end of the second year= 

363650.

Let the cost price of each mango be Rs. 1

So 50 mangoes costs = Rs. 50

20% Profit on Selling Price of 10 mangoes = Rs. 12 

30% Profit on Selling Price of 20 mangoes = Rs. 26

Total = Rs. 38

Loss = 50 - 38 = 12

Loss% = (12/50) x 100 = 24%.

Mass of zinc ore = 8000 kg

Mass of metal = 60% of 8000 = 4800 kg

Mass of silver in metal = 3/4 x 4800/100 = 36 kg

Mass of zinc = 4800 - 36 = 4764 kg.

Literally any percentage means divide by 100.

So 125% = 125100. That can be reduced to 5/4.

To convert to a decimal, you can do long division, dividing 5 into 4.