Directions: Find the wrong number in the following number series:

2, 6, 10, 19, 36, 69, 134

Directions: The line graph shows the number of work visas issued by a country in each year from 2011 to 2016. Study the diagram and answer the following questions . 

What is the total number of visas issued from 2012 to 2015 ? 

P can do a piece of work in 60 days & Q can do the same work in 50 days. Find the ratio of working efficiencies of P to Q.

If the average marks of three batches of 55, 60 and 45 students respectively is 50, 55 and 60, then the average marks of all the students is?

A secant PAB is drawn from an external point P to the circle with centre O, intersecting it at A and B. If OP = 17 cm, PA = 12 cm and PB = 22.5 cm, then the radius of the circle is:

While selling an article, a shopkeeper gives a discount of 5%. If he gives a discount of 7%, he earns Rs.15 less as profit. The marked price of the article is -

The length of a rectangle is increased by 60% then by how much % should the breadth be reduced so that its area does not change?

In a school, if there are 36% boys and 352 girls, then the number of boys is ________.