Direction : What should come in place of the question (?) in the following question.

8934 – 3257 + 481 = ? + 2578

How many numbers are there from 500 to 650 (including both) which are neither divisible by 3 nor by 7?

Direction : What should come in place of the question (?) in the following question.

8424÷ 135 ×6=?

The difference of a number consisting of two digits from the number formed by inter changing the digits is always divisible by: 

The total cost of 18 pens and 23 pencils is Rs. 231, while the total cost of 7 pens and 13 pencils is Rs. 102. What is the cost of 4 pens and 9 pencils?

N is the smallest three digit prime number. When N is divided by 13, then what will be the remainder? 

0.1 and   $${5\over 8}$$ of a bamboo are in mud and water respectively and the rest of length 2.75 m is above water. What is the length of the bamboo? 

How many two-digit numbers are divisible by 3 but not by 7?