Percentage Questions

Let the rquired number be 'P'

According to the question,

$$\begin{gathered} 100 x P100 = 20 \\ => P = 20 x 100100 = 20 \end{gathered}$$

Hence, 100 percent of the number 20 is 20.

Now, you can also try for

20 percent of what number is 100

$$\begin{gathered} 20 x P100 = 100 \\ => P = 100 x 10020 = 500 \\ => P = 500 \end{gathered}$$

Hence, 20 percent of the number 500 is 100.

63.5% of 8924.2 +? % of 5324.4 = 6827.5862

=> 63.5% of 8925 + ? % of 5325 = 6830

=> 6830 ~= 5320 + ?(5325)/100

=> ? ~= 22

n (A) = (60/100 * 96) = 288/5, n (B) = (30/100 * 96) = 144/5, n (A ∩ B) = (15/100 * 96) = 72/5.

n(A ∪ B) = n (A) + n (B) - n (A ∩ B) = 72.

So, people who had either or both types of lunch = 72.

Hence, people who had neither type of lunch = (96 - 72)= 24.

Here 85 of 352 => 85 is what percent in 352

Let p% of 352 is 85

Percentage(%) is generally calculated in the total of 100.

=> p x 352/100  = 85

=> p = 8500/352  = 24.14%

Hence, 85 is 24.14% of 352.

End of first year     :  10000 x (3/5) = Rs. 6000
End of second year :  6000 x (3/5) = Rs. 3600
End of third year    :  3600 x (3/5) = Rs. 2160

Let number of pages in a book = p

According to questions

p - [3p/7 + (2/5 x 4p/7)] = 36

= p - 23p/35 = 36

=> 12p = 36 × 35

p = 105

Let N be the required number. 

=> 60100x27x34xN=2664  

=> N = 2664x2x7x5/9  

=> N = 20720.