Two circle X and Y with centres A and B intersect at C and D. If area of circle X is 4 time area of circle Y, then AB=?

A circle touches a quadrilateral ABCD. Find the true statement: -

The number of students in three classes are in the ratio 2:3:5. If the number of students in each class is increased by 20 the ratio become 4: 5: 7. The total number of students before the increase was

If $$ {81\ × 343\ ×625}={3^{p}}\ {7^{q}}\ {5^{r}}$$ then find out the value of  $$ {\sqrt{(p-r)^{2}+q^{2}}}$$.

Find out the value of $$ {\sqrt{(121)}} +{\sqrt{(12321)}}+{\sqrt{(1234321)}}$$.

If a : b = 20:5 then find out the value of (13a-9b): (11a-7b)?

In a exam, a student scores four marks for every correct answer and loses one mark for every wrong answer. If Rahul attempts all sixty questions and secures 130 marks, the no of questions Rahul attempted correctly is :

Mr. Kulbhushan spends 35% of his income on food, 25% on transportation and 80% of the remaining on house rent. What percent of his income he is left with?