Average


  1. A person covers 9 km with a speed of 3 km/h, 25 km with a speed of 5 km/h and 30 km with a speed of 10 km/h. Find out the average speed of person.











  1. View Hint View Answer Discuss in Forum

    Here, P = 9 km/h, Q = 25 km/h, R = 30 km
    x = 3 km/h, y = 5 km/h and z = 10 km/h
    ∴ Required average speed
    = [P + Q + R] / [(P/x) + (Q/y) + (R/z)]

    Correct Option: A

    Here, P = 9 km/h, Q = 25 km/h, R = 30 km
    x = 3 km/h, y = 5 km/h and z = 10 km/h
    ∴ Required average speed
    = [P + Q + R] / [(P/x) + (Q/y) + (R/z)] = [9+25 + 30] / [(9/3) + (25/5) + (30/10)]
    = 64/(3 + 5 + 3)
    = 64/11
    = 59/11 km/h


  1. The daily minimum temperature of a place in a certain week. begining from Monday was 20°, 18.6°, 17°, 21.4°, 19° and 19.8°. It was known that the average of whole week was 19.5°. The minimum temperature on Sunday was ?









  1. View Hint View Answer Discuss in Forum

    Let temperature on sunday be x° C.
    (20° + 18.6° + 17° + 21.4° + 19° + 19.8° + x) / 7 = 19.5°

    Correct Option: C

    Let temperature on sunday be x° C.
    (20° + 18.6° + 17° + 21.4° + 19° + 19.8° + x) / 7 = 19.5°
    ⇒ 115.8 + x = 19.5 x 7
    ⇒ x = 136.5 - 11.58
    ⇒ x = 20.7°C



  1. Average weight of three boys P, T and R is 541/3 kg, while the average weight of three boys T, F and G is 53 kg. What is the average weight of P, T, R, F and G ?











  1. View Hint View Answer Discuss in Forum

    According to the question
    (P + T + R) / 3 = 541/3
    ⇒ P + T + R = (163/3) x 3
    ⇒ P + T + R = 163 ............(i)
    Also (T + F + G)/3 = 53
    ⇒ T + G + F = 159 ..........(ii)

    Correct Option: D

    According to the question
    (P + T + R) / 3 = 541/3
    ⇒ P + T + R = (163/3) x 3
    ⇒ P + T + R = 163 ............(i)
    Also (T + F + G)/3 = 53
    ⇒ T + G + F = 159 ..........(ii)
    Clearly, from the two Eqs. (i) and (ii), the problem cannot be solved.


  1. The average runs scored by a cricketer is 42 innings, is 30. The difference between his maximum and minimum scores in an inning is 100. If these two innings are not taken into consideration, then the average score of remaining 40 inning is 28. Calculate the maximum runs scored by him in an innings ?









  1. View Hint View Answer Discuss in Forum

    Let the minimum score = x
    ∴ Maximum score = x + 100
    ∴ x + (x + 100) = 30 x 42 - 40 x 28

    Correct Option: B

    Let the minimum score = x
    ∴ Maximum score = x + 100
    ∴ x + (x + 100) = 30 x 42 - 40 x 28
    ⇒ 2x + 100 = 1260 - 1120 = 140
    ⇒ 2x = 140 - 100 = 40
    ⇒ x = 20
    Hence, the maximum score = x + 100
    = 20 + 100 = 120



  1. A car reached Raipur from Somgarh in 35 min With an average speed of 69 km/h. If the average speed is increased by 36 km/h, how much time will it take to cover the same distance ?











  1. View Hint View Answer Discuss in Forum

    Distance between Raipur and Somgarh
    = Average speed x Time
    = 69 x 35/60= 161/4 km
    New speed = (69 + 36) km/h = 105 km/h
    ∴ Time = Distance/ Speed = 161/4 x 105 h
    = 161 x 60/4 x 105min = 23 min

    Correct Option: C

    Distance between Raipur and Somgarh
    = Average speed x Time
    = 69 x 35/60= 161/4 km
    New speed = (69 + 36) km/h = 105 km/h
    ∴ Time = Distance/ Speed = 161/4 x 105 h
    = 161 x 60/4 x 105min = 23 min