11.
In an institute of 20 boys in an exam in Maths 2 boys scored 100 marks each, 3 got zero each and the average of the rest was 40. What is the average of the whole institute?
- A.40 Marks
- C.32 Marks
- B.35 Marks
- D.45 Marks
- Answer & Explanation
- Report
Answer : [A]
Explanation :
Explanation :
| Marks scored by 2 boys = 100 x 2 = 200 | ||||||||||
| Marks scored by 3 boys = 3 x 0 = 0 | ||||||||||
| Marks scored by 15 boys = 15 x 40 = 600 | ||||||||||
| Marks scored by 20 boys = 200 + 0 + 600 = 800 |
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12.
The average weight of 8 mariners in a vessel is increased by 1 kg if one of them weighing 56 kg is replaced by a new mariner. The weight of the new mariner is
- A.57 kg
- C.64 kg
- B.60 kg
- D.62 kg
- Answer & Explanation
- Report
Answer : [C]
Explanation :
Explanation :
| The sailor weighing 56 kg is replaced and the average is increased by 1 kg. |
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| Hence, the weight of the new sailor is (56 + increase in total weight) = 56 + 1 x 8 | |||
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13.
The average salary per head of all the staffs in a factory is Rs. 850, If the average salary per head of 7 technicians is Rs 1000 and the average salary per head of the rest is Rs 780, find the total number of staffs in the factory.
- A.26
- C.28
- B.24
- D.22
- Answer & Explanation
- Report
Answer : [D]
Explanation :
Explanation :
| Let the total number of staffs be x | |||||
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14.
The daily earnings of a Book seller during a week are : Rs. 70, Rs. 52.50, Rs. 60, Rs. 63, Rs. 68, Rs. 65, and Rs. 73. What is his average daily earning for the week?
- A.Rs. 74.50
- C.Rs. 64.50
- B.Rs. 54.50
- D.Rs. 84.50
- Answer & Explanation
- Report
Answer : [C]
Explanation :
Explanation :
| Total earning for 7 days |
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15.
The sum of 3 numbers is 98. If the ratio between 1st and 2nd be 2:3 and that between 2nd and 3rd be 5:8, then the 2nd number is
- A.30
- C.58
- B.20
- D.48
- Answer & Explanation
- Report
Answer : [A]
Explanation :
Explanation :
| Let the numbers be x, y and z, Then | ||||||||||||||||||||
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