Discussion
Home ‣ Aptitude ‣ Average Comments
- Question
- The average of 13 result is 68. The average of first seven is 63 and that of the last seven is 70 , the seventh result is?
Options- A. 47
- B. 65.5
- C. 73.5
- D. 94
- Correct Answer
- 47
ExplanationSeventh Result = sum of first 7 results + sum of last 7 results - sum of all 13 results.
? Seventh Result = (7 x 63) + (7 x 70) - (13 x 68 )
=47 - 1. The average of 10 number is calculate as 15. It is discovered later on that while calculating the average one number , namely 36 was wrongly read as 26. The correct average is?
Options- A. 12.4
- B. 14
- C. 16
- D. 18.6 Discuss
- 2. With an average speed of 40km/hr. a train reached its destination in time. If it goes whith an average speed of 35km/hr, it is late by 15 minute . The total journey is?
Options- A. 30 km
- B. 40 km
- C. 70 km
- D. 80 km Discuss
- 3. On a journey across Delhi, a taxi average 30 kmph for 60% of the distance, 20 kmph for 20% of it and 10 kmph for the remainder, the average speed for the whole journey is?
Options- A. 20 km/hr
- B. 22.5 km/hr
- C. 24.625 km/hr
- D. 25km/hr Discuss
- 4. The average of odd number upto 100 is?
Options- A. 51
- B. 50
- C. 49.5
- D. 49 Discuss
- 5. The average age of three boys is 15 years.if their ages are in the ratio 3: 5: 7, the age of the youngest boys is?
Options- A. 3 year
- B. 15 year
- C. 18 year
- D. 21 year Discuss
- 6. The average of 25 results is 18, that of first twelve is 14 and of last twelve is 17 . Thirteenth result is?
Options- A. 28
- B. 72
- C. 78
- D. 85 Discuss
- 7. The average temperature of Monday, Tuesday, Wednesday, and Thursday was 38° C and that of Tuesday, Wednesday, Thursday and Friday was 40° C, if the temperature on Monday was 30° C, the temperature of Friday was?
Options- A. 40°
- B. 39°
- C. 38°
- D. 30° Discuss
- 8. The average of 5 consecutive number is n , if the next two number are also include, the average of 7 number will?
Options- A. Increase by 2
- B. increase by 1
- C. Remains the same
- D. Increase by 1.4 Discuss
- 9. A man whose bowling average is 12.4 takes 5 wicket for 26 runs and thereby decreases his average by 0.4. The number of wickets taken by him, before his last match is?
Options- A. 85
- B. 78
- C. 72
- D. 64 Discuss
- 10. There were 35 students in a hostel. If the number of students increased by 7, the expenses of the mess were increase by Rs 42 per Day , while the average expenditure per head diminished by Re. 1 The original expenditure of the mess was?
Options- A. Rs. 40
- B. Rs . 420
- C. Rs . 432
- D. Rs . 442 Discuss
Average problems
Search Results
Correct Answer: 16
Explanation:
New sum of numbers = previous sum - 26 + 36
=10 x 15 - 26 + 36
= 160
? Correct Average = 160 / 10 = 16.
Correct Answer: 70 km
Explanation:
Let total journey be y km.
From question y/35 - y/40= 15/60
? y = ( 35 x 40 )/ ( 4 x 5 ) = 70
? Total Journey = 70 km
Correct Answer: 20 km/hr
Explanation:
Let total journey = y km
Total time taken = time taken during 60% of distance + time taken during 20% of distance + time taken in remaining distance
= [( 60y / 100 ) / 30] + [( 20y / 100 ) / 20] + [( 20y / 100 ) / 10]
= ( y / 50 + y / 100 + y / 50 )hrs
= y/20 hours.
Average speed = total distance traveled / total time taken.
= [y / ( y/20 )] km/hr
=20 km/hr.
Correct Answer: 50
Explanation:
sum of odd number upto 100 = 1 + 3 + 5 + 7+....+ 95 + 97 + 99
=(1+99) + (3+97) + (5+95) +.... upto 25 terms
= 100 + 100 + 100 +.... upto 25 terms
= 2500
Average = 2500 /50
= 50
Correct Answer: 3 year
Explanation:
Age of A : age of B : age of C = 3 : 5 : 7
So the average age of 3 boys (3x + 5x + 7x ) /3 = 15
?15x= 15 x 3
? x= 3
Correct Answer: 78
Explanation:
Thirteenth Result = sum of all 25 results - sum of first 12 results - sum of last 12 results.
= 25 x 18 - 12 x 14 ? 12 x 17
=78
Correct Answer: 38°
Explanation:
From question
M + T + W + TH = 4 x 38° = 152°
? T + W + TH =152° ? 30° = 122°
Again from question
? T + W + TH + F = 4 x 40° = 160°
? F = 160° ? 122°
= 38°
Correct Answer: increase by 1
Explanation:
Sum of 5 consecutive integers
x + ( x +1 ) + ( x +2 ) + ( x + 3 ) + ( x +4 ) = 5n
? 5x + 10 = 5n
? x = ( n ? 2 ) ......(i)
Average of 7 consecutive integers
= [( 5x + 10 ) + ( x + 5 ) + ( x + 6 )] / 7
= 7x + 21 / 7
= x + 3 .....(ii)
from eq. (i) and (ii)
New average = x + 3 = ( n ? 2 + 3 ) = n + 1
So , the new average increases by 1 .
Correct Answer: 85
Explanation:
Let the number of wickets taken before the last match = y
Bowler's overall average = total run scored / total wicket taken by bowler
Then, (12.4y + 26 ) / (y + 5) = 12
? x = 85
Correct Answer: Rs . 420
Explanation:
Let the original expenditure be Rs. y per day ,
Then, y / 35 - [( y + 42 ) / 42 ] = 1
? 42y - 35 ( y + 42 ) = 35 x 42
? 7y = 35 x 42 + 35 x 42
? y = ( 2 x 35 x 42 ) / 7
= 420
Hence , the original expenditure is Rs . 420
Comments
There are no comments.More in Aptitude:
Programming
Copyright ©CuriousTab. All rights reserved.