Quiz Discussion

The mean high temperature of the first four days of a week is 25°C whereas the mean of the last four days is 25.5°C. If the mean of the whole week is 25.2°C then the temperature of the 4th day is :

• 1] 25°C
• 2] 25.2°C
• 3] 25.6°C
• 4] 25.5°C

The average monthly salary of 660 workers in a factory is Rs. 380. The average monthly salary of officers is Rs. 2100 and the average monthly salary of the other workers is Rs. 340. Find the number of other workers.

• 1] 645
• 2] 650
• 3] 640
• 4] 642

The average of 20 numbers is zero. Of them, at the most, how many may be greater than zero ?

• 1]

  0

• 2]

  -1

• 3]

  1

• 4]

  None Of These

If the arithmetic mean of 7, 5, 13, x and 9 is 10, then the value of x is :

• 1] 10
• 2] 12
• 3] 14
• 4] 16

If the average of 5 consecutive integers is x then, find the average of next to next 5 consecutive integers.

• 1] x + 5
• 2] x - 5
• 3] x + 10
• 4] x + 25

The average salary of all the workers in a workshop is Rs.8000. The average salary of 7 technicians is Rs.12000 and the average salary of the rest is Rs.6000. The total number of workers in the workshop is

• 1]

  20

• 2]

  21

• 3]

  22

• 4]

  23

There are 30 students in a class. The average age of first 10 students is 12.5 years. The average age of the remaining 20 students is 13.1 years. The average age (in years) of the students of the whole class is :

• 1] 12.5 years
• 2] 12.7 years
• 3] 12.8 years
• 4] 12.9 years

One-fourth of certain journey is covered at the rate of 25 km/h, one-third at the rate of 30 km/h and the rest at 50 km/h. Find the average speed for the whole journey.

• 1]

  600/53 km/h

• 2]

  1200/53 km/h

• 3]

  1800/53 km/h

• 4]

  1600/53 km/h

• 5]

  None of these

Find the average of 205, 302, 108, 403, and 202-

• 1] 450
• 2] 1125
• 3] 244
• 4] 1220

The average of 20 students is 12 years, if the teacher's age is included, average increases by one. The age of the teacher is:

• 1] 30 years
• 2] 33 years
• 3] 28 years
• 4] 35 years