Simplify  $$ ^{3}\sqrt{-2197} × ^{3}\sqrt{{-125}} \ ÷ ^{3}\sqrt{27\over512}$$.

The bar graph shows the number of passports issued in a country in 6 consecutive years.

What is the average number of passports issued per year?

What is compound interest on a sum of Rs. 37,500 for $$ {1{1\over 3}}$$ years at a rate of 12 % per year. If the interest is compounded 8 monthly?

What will be come in place of question mark(?) in the following number series?
14, 8, 7 , 11.5, 22, ?

The ratio of milk and water in to mixtures A and B are 3:4 and 5:9 respectively. If these two mixtures are mixed in the ratio of 2:3. Then find the ratio of milk and water in the resultant mixture. 

The HCF of two numbers is 4 and the two other factors of LCM are 5 and 7. Find the smaller of the two numbers.

The age of a mother 10 years ago was thrice the age of her son. 10 years hence, the mother's age will be twice that of 9 her son. The ratio of their present ages is :

The interior angle of a regular polygon exceeds its exterior angle by $$90^0$$. The number of sides of the polygon is: