Harmonic mean - math problems

Number of problems found: 110

  • A frequency
    frequency-and-wavelength A frequency table of grades has five classes (A, B, C, D, F) with frequencies of and 2,14,13,8 and 1 respectively. Using percentages, what are the relative frequencies of the five classes?
  • Average speed
    speed The car drove on one section of the highway for half an hour at a speed of 80 km/h. Then he reduced his speed to 60km/h. It went three-quarters of an hour at a speed of 60 km/h. What was the average speed of the car?
  • Workshops
    workers The plant has three workshops. In the first workshop, produce 5 products/hour, in the second 8 products/hour, and in the third 7 products/hour. In the first workshop, they produced 240 products, in the second 400 and the third 350 products. Find the avera
  • Two cables
    pole On a flat plain, 2 columns are erected vertically upwards. One is 7 m high and the other 4 m. Cables are stretched between the top of one column and the foot of the other column. At what height will the cables cross? Assume that the cables do not sag.
  • Average speed
    cars The car drove from city A to city B at a 40 km/h and back to city A at a speed of 80 km/h. What was the average speed of the car?
  • Statistical survey
    statistics Write TRUE OR FALSE for each question: 1 Standard deviation is a measure of central location. 2. The most frequent observation in a data set is known as the mode. 3 The most passive method of data collection is observation. 4 Access time for secondary dat
  • Weighted harmonic average
    workers Ten workers will do some work in 2 minutes, five workers in 10 minutes and three workers in 6 minutes. How many minutes per average worker per worker?
  • Harmonic mean
    means_math If x, y, z form a harmonic progression, then y is the harmonic mean of x and z. Find the harmonic mean of the numbers 6 and 5.
  • Harmonic series
    mean_normal Insert four members between 5/3 and 5/11 to form harmonic series (means).
  • Insert 7
    seq Insert five harmonic means between 3 and 18
  • Insert 6
    seq Insert four harmonic means between 3/7 and 3/19
  • Insert 5
    sequence_geo Insert five harmonic means between 1/2 and 1/26
  • Harmonic HM example
    mean_normal Find the harmonic mean of 4 and 8.
  • Harmonic 4
    mean_normal The harmonic mean of -6 and 5.
  • Harmonic mean
    sequence_geo Harmonic means of 6 and 12
  • HP - harmonic progression 2
    seq Compute the 16th term of the HP if the 6th and 11th term of the harmonic progression are 10 and 18 respectively.
  • HP - harmonic progression
    exp_growth Determine the 10th term of the harmonic progression 6,4,3,…
  • Statistics quiz
    normal_d Fill in the missing word 1. in a data set, the mean, median and mode are measured of ________________ 2. "The manipulation of variables under controlled conditions"is the data collection method known as______________ 3. in a normal distribution, the area
  • The leaves
    garden Karel would rake the leaves in the garden alone in 24 minutes, his younger brother would take 30 minutes. How long would they dig a garden, if Karel digs alone for 6 minutes and then his brother comes to his aid?
  • Aircraft angines
    aircraft-02 The two engines of the aircraft are enough to supply the fuel for five hours of operation. However, one of the engines has a malfunction and thus consumes one-third more fuel. How long can the plane be in the air before it runs out of fuel? After an hour

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