Find the average of the first 5 odd numbers.

The average of 5 numbers is 7. The sum of four of the numbers is 24. Find the fifth number.

What is the average time of the two fastest boys?

Mr Sim sold an average of 25 curry puffs per day from Monday to Friday. He sold a total of 47 curry puffs on Monday and Tuesday. What was the average number of curry puffs he sold from Wednesday to Friday?

The average of three numbers is 12. The sum of the two if the numbers is twice that of the third number. What is the third number?

Alan, Bob, Charlie and Donald have an average mass of 58 kg. The combined mass of Alan and Bob is 28 kg more than the combined mass of Charlie and Donald. Alan’s mass is 49 kg, what is Bob’s mass?

The average of two numbers X and Y is 28. The ratio of X to Y is 5 : 2. What is the difference between the two numbers?

Mr Loo recorded the test scores for a class of 20 pupils and found the average score to be 80 marks. Upon checking, he realised he had incorrectly recorded a score of 80 marks as 40 marks. What should the correct class average score be?

A 3-cabin train on the Express Line has an average number of 190 passengers per cabin. The first cabin has 50 more passengers than the third cabin. The second cabin has twice as many passengers as the third cabin. How many passengers are there in the second cabin?

The average number of sweets in 5 boxes was 47. When Sally took one box of sweets away, the average number of sweets in the remaining boxes became 49. How many sweets did Sally take?