The average of twelve numbers is 45.5. The average of the first four numbers is 41.5 and that of the next five numbers is 48. The 10th number is 4 more than the 11th number and 9 more than the 12th number. What is the average of the 10th and 12th numbers?
Average of 12 numbers = 45.5 Sum of 12 numbers = 45.5 × 12 = 546 Average of first 4 numbers = 41.5 Sum of first 4 numbers = 41.5 × 4 = 166 Average of next 5 numbers = 48 Sum of next 5 numbers = 48 × 5 = 240 Sum of 10th, 11th and 12th number = 546 – 166 – 240 = 140 Let the 10th number be x. 11th number = x – 4 12th number = x – 9 According to the question, => x + x – 4 + x – 9 = 140 ⇒ 3x – 13 = 140 ⇒ 3x = 140 + 13 ⇒ 3x = 153 ∴ x = 153/3 = 51 Average of 10th and 12th number = (51 + 51 – 9)/2 = 93/2 = 46.5
If the temperature of a place increases suddenly, the relative humidity –
The correct option, if speeds of gamma rays, X-rays and microwave are Vg, Vx an Vm respectively will be
The surface tension of water on adding detergent to it –
Why does a fountain pen leak on an airplane flying at high altitude?
In an electric motor, energy is transformed from:
Which of the following statement is INCORRECT regarding the comparison between biot-savart law for the magnetic field and coulomb's law for the electro...
Which of the following statement is correct?
I. Value of ‘g’ is higher at poles than equator
II. Weight of an object at moon is 1...
A copper block of mass 3 kg is heated in a furnace to a temperature of 450°C and then placed on a large ice block. Find the maximum amount of ice that...
A pulse of light duration 10-5 s is absorbed fully by a little object initially at rest. If the power of this pulse is 45 × 10-3...
A pond of water appears less deep due to –
