Problem Solving MCQ Set 6

Question: Three math classes: X, Y, and Z, take an algebra test.
The average score in class X is 83.
The average score in class Y is 76.
The average score in class Z is 85.
The average score of all students in classes X and Y together is 79.
The average score of all students in classes Y and Z together is 81.
What is the average for all the three classes?

1. 81
2. 81.5
3. 82
4. 84.5

Question: The average weight of a class of 24 students is 36 years. When the weight of the teacher is also included, the average weight increases by 1kg. What is the weight of the teacher?

1. 60 kgs
2. 61 kgs
3. 37 kgs
4. None of these

Question: The average of 5 quantities is 10 and the average of 3 of them is 9. What is the average of the remaining 2?

1. 11
2. 12
3. 11.5
4. 12.5

Question: The average age of a family of 5 members is 20 years. If the age of the youngest member be 10 years then what was the average age of the family at the time of the birth of the youngest member?

1. 13.5
2. 14
3. 15
4. 12.5

Question: A student finds the average of 10 positive integers. Each integer contains two digits. By mistake, the boy interchanges the digits of one number say ba for ab. Due to this, the average becomes 1.8 less than the previous one. What was the difference of the two digits a and b?

1. 8
2. 6
3. 2
4. 4

Question: Average cost of 5 apples and 4 mangoes is Rs. 36. The average cost of 7 apples and 8 mangoes is Rs. 48. Find the total cost of 24 apples and 24 mangoes.

1. 1044
2. 2088
3. 720
4. 324