Find the ratio of the following:

(a) Speed of a cycle 15 km per hour to the speed of scooter 30 km per hour.

(b) 5 m to 10 km

(c) 50 paise to Rs 5

Convert the following ratios to percentages.

(a) 3 : 4 (b) 2 : 3

72% of 25 students are good in Mathematics. How many are not good in Mathematics?

A football team won 10 matches out of the total number of matches they played. If their win percentage was 40, then how many matches did they play in all?

If Chameli had Rs 600 left after spending 75% of her money, how much did she have in the beginning?

If 60% people in a city like cricket, 30% like football and the remaining like other games, then what per cent of the people like other games? If the total number of people are 50 lakh, find the exact number who like each type of game.

What is the percentage of 5 oranges out of 25 fruits?

A picnic is being planned in a school for class VIII. Girls are 60% of the total number of students and are 18 in number. 
(A) What is the total strength of the class?
(B) What is the ratio of the number of boys to the number of girls?
   
If the picnic spot is 55 km from the school and their first stop is at 22 km from the school, what percent of the total distance is this?

Rahul got 150 marks out of 200 and Prabha got 180 marks out of 300. Whose performance is better?

18% of a class took part in a karate competition. If 18 students have taken part in it, then what is the total number of students in the class?