48
Q:

# A batsman makes a score of 87 runs in the 17th inning and thus increases his average by 3. Find his average after 17th inning?

Q:

The average monthly salary of the employees of a firm is Rs.60 out of the employees 12 officers get an average of Rs.400 per month and the rest an average of Rs. 56 per month , Find the number of emp

Actual average salary of 12 officers = 400

$\inline&space;\fn_jvn&space;\therefore$ Total salary of 12 officers = 400 x 12 = 4800

Average of these 12  officers as a whole =60

Total salary of 12 officers as a whole = 60 x 12 = 720

The total salary of rest  = 4800 - 720 = 4080

Difference in average of the rest of officers  = 60 - 56 = 4

Rest of the officers = $\inline&space;\fn_jvn&space;\frac{4080}{4}=1020$

Total number of employees = 1020 + 12 = 1032

1032
Q:

The mean temperature of Monday to Wednesday was 37C and of Tuesday to Thursday was 34C . If the temperature on Thursday was (4/5) th that of Monday, the temperature on Thursday was?

$\inline&space;\fn_jvn&space;M+T+W&space;=(37\times&space;3)^{0}=111^{0}C$   -----------(1)

$\inline&space;\fn_jvn&space;T+W+Th=(34\times&space;3)^{0}=102^{0}C$

$\inline&space;\fn_jvn&space;\Rightarrow&space;T+W+\frac{4}{5}M&space;=&space;102^{0}C$                --------------(2)

(1) - (2) gives

$\inline&space;\fn_jvn&space;\frac{1}{5}$ th of temperature on Monday = $\inline \fn_jvn 111^{0}-102^{0}=9^{0}C$

$\inline&space;\fn_jvn&space;\Rightarrow$ Temperature on Monday = $\inline&space;\fn_jvn&space;45^{0}C$

$\inline&space;\fn_jvn&space;\therefore$ Temperature on Thursday = $\inline&space;\fn_jvn&space;\frac{4}{5}\times&space;45^{0}=36^{0}$

4239
Q:

The average of 9 results is 50. The average of first four results is 52 and average of last four results is 49 . what is the fifth result?

Total of results = 50 x 9 = 450

Total of first four results = 52 x 4 = 208

Total of Last four results = 49 x 4 = 196

Hence the fifth result = 450 - (208 + 196) = 46

799
Q:

A man covers a journey from Meerut to Delhi by a car at an average speed of 40 km/hr. He returns back by scooter with an average speed 24 km/hr. Find his average speed during the whole journey?

Average speed = $\inline \fn_jvn \frac{2xy}{x+y}$ km/hr

=  $\inline \fn_jvn \frac{2\times 40\times 24}{40+24}=30$ km/hr

674
Q:

The average expenditure of the hotel when there are 10 guests is Rs. 60 per guests and the average expenditure is Rs.40 when there are 20 Guests. If it is known that there are some fixed expenses irrespective of the number of guests then the average expenditure per guest  whe there are 40 guests in the hotel.

 A) Rs. 30 B) Rs. 25 C) Rs. 20 D) can't be determined

Explanation:

Let the fixed expenditure of the hotel be Rs.x and the variable expenditure ( which is dependent on the guest ) is Rs.y , then

x + 10y = 600        ---------(1)

x + 20y = 800       ----------(2)

$\inline&space;\Rightarrow$              10y = 200

y = Rs. 20   and    x= 400

Hence the total expenditure when there are 40 guests = 400 + 40 x 20 = 1200

$\inline&space;\therefore$ average expenditure = $\inline&space;\frac{1200}{40}$ = Rs. 30