Quiz Discussion

The average age of three boys is 15 years. If their ages are in ratio 3 : 5 : 7, the age of the youngest boy is

• 1] 21 years
• 2] 18 years
• 3] 15 years
• 4] 9 years
• 5] 12 years

The average marks of four subjects is 120. If 33 was misread as 13 during the calculation, what will be the correct average?

• 1] 122
• 2] 120
• 3] 125
• 4] 121

The average income of A, B and C is Rs. 12,000 per month and average income of B, C and D is Rs. 15,000 per month. If the average salary of D be twice that of A, then the average salary of B and C is in Rs. :

• 1] 8,000
• 2] 18,000
• 3] 13,500
• 4] 9,000

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

The average temperature for Wednesday, Thursday and Friday was 40°C. The average for Thursday, Friday and Saturday was 41° C. If temperature on Saturday was 42° C, what was the temperature on Wednesday?

• 1] 39° C
• 2] 44° C
• 3] 38° C
• 4] 41° C

The average of first five multiples of 3 is:

• 1] 9
• 2] 10
• 3] 8
• 4] 11

A student finds the average of 10, 2 digits numbers. If the digits of one of the numbers interchanged, the average increases by 3.6. The difference between the digits of the 2 digits number is :

• 1] 4
• 2] 3
• 3] 2
• 4] 5

A man has 'n' magical eggs whose average weight is 'k' gm. Each of the 'n' eggs produces 'n' eggs next day such that the average weight of 'n' eggs produced is same as that of the parental egg for each 'n' groups individually i.e. each egg produces 'n' eggs of next generation and average weight of all the 'n' eggs of next generation is same as the weight of the mother egg. This process is continued without any change in pattern. What is the total weight of all the eggs of rth generation, where the initial number of eggs with man are considered as the eggs of first generation.

• 1] rnk
• 2] rnk
• 3] nkr
• 4] nrk
• 5] None of these

The average of 6 observations is 45.5. If one new observation is added to the previous observations, then the new average becomes 47. The new observation is :

• 1] 58
• 2] 56
• 3] 50
• 4] 46

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