The average age of 31 students of a class is 30 years. If the age of the teacher is also included, the average age of the whole group becomes 31 years. The age (in years) of the teacher is:
Given:
Average age of 31 students = 30 years
Average age of 32 people (including teacher) = 31 years
Formula Used:
Sum = Average × Number of Observations
Solution:
Sum of ages of 31 students = 31 × 30 = 930
Sum of ages of 32 people = 32 × 31 = 992
Age of the teacher = Sum of 32 people - Sum of 31 students
Age of the teacher = 992 - 930 = 62
Final Answer
So the correct answer is (a)
English
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90 Mins English English100 Questions100 Marks90 Mins English English100 Questions100 Marks90 Mins EnglishThe average age of 31 students of a class is 30 years. If the age of the teacher is also included, the average age of the whole group becomes 31 years. The age (in years) of the teacher is:
The average of 13 numbers is 7. If each number is multiplied by 2, then what will the new average be?
A cricketer has an average of 88 runs over 10 innings. If he scores 219 runs in the 11th inning, by how many runs (rounded off to the nearest whole number) does his average score increase?
A cricketer has an average of 68 runs over 9 innings. If he scores 130 runs in the 10th inning, by how many runs (rounded off to the nearest whole number) does his average score increase?
A cricketer has an average of 62 runs over 5 innings. If he scores 296 runs in the 6th inning, by how many runs does his average score increase?
A class of 93 students took a Physics test. 10 students had an average score of 90. The remaining students had an average score of 75. What is the average score (rounded off to one decimal place) of the whole class?
A cricketer has an average of 57 runs over 10 innings. If he scores 195 runs in the 11th inning, by how many runs (rounded off to the nearest whole number) does his average score increase?
A stationery shop sells premium, standard, and basic pens at ₹15, ₹10, and ₹5 each, respectively. The pens are sold in the ratio 3 : 2 : 5. What is the average selling price (in ₹) of a pen?
The average of 11 results is 61. If the average of the first 6 results is 64 and that of the last 6 is 61, find the 6th result.
Let five odd consecutive natural numbers are P,Q,R,S and T . What is their average ？
Suggested Test Series
Suggested Test Series
The average age of 31 students of a class is 30 years. If the age of the teacher is also included, the average age of the whole group becomes 31 years. The age (in years) of the teacher is:
The average of 13 numbers is 7. If each number is multiplied by 2, then what will the new average be?
A cricketer has an average of 88 runs over 10 innings. If he scores 219 runs in the 11th inning, by how many runs (rounded off to the nearest whole number) does his average score increase?
A cricketer has an average of 68 runs over 9 innings. If he scores 130 runs in the 10th inning, by how many runs (rounded off to the nearest whole number) does his average score increase?
A cricketer has an average of 62 runs over 5 innings. If he scores 296 runs in the 6th inning, by how many runs does his average score increase?
A class of 93 students took a Physics test. 10 students had an average score of 90. The remaining students had an average score of 75. What is the average score (rounded off to one decimal place) of the whole class?
A cricketer has an average of 57 runs over 10 innings. If he scores 195 runs in the 11th inning, by how many runs (rounded off to the nearest whole number) does his average score increase?
A stationery shop sells premium, standard, and basic pens at ₹15, ₹10, and ₹5 each, respectively. The pens are sold in the ratio 3 : 2 : 5. What is the average selling price (in ₹) of a pen?
The average of 11 results is 61. If the average of the first 6 results is 64 and that of the last 6 is 61, find the 6th result.
Let five odd consecutive natural numbers are P,Q,R,S and T . What is their average ？
