The average of a,b,c is 20 and that of b,c,d is 25, if d=30, then the value of a is-

$$ {I.2x^{2}-{9x}+10=0}$$
$$ {II.2y^{2}-13y+20=0}$$

If 40% of (A+B) = 60% of (A-B) then $${2A-3B}\over {A+B}$$ is

Rewa has some hens and some goats. If the total number of animal heads is 100 and the total number of animal feet is 348, then what is the total number of goats with Rewa? 

The simple interest on a sum  of money is $$8\over 25$$ of the sum. If the number of years is numerically half the rate percent per annum, then the rate percent per annum is 

Of the three numbers whose average is 60, the first is one-fourth of the sum of the whole number. The first number is: 

Direction: Study the following table carefully and answer the given questions. Table shows the of passed students in four schools and ratio between passed boys and girls among them. The ratio between failed boys and girls is reverse of passed ratio between them.

If the difference between the failed boys and girls is 25 in school S, then find the ratio between passed and failed students in School S?

Find the compound interest to the nearest rupee on Rs. 7500 for 2 years 4 months at 12% p.a reckoned annually?