Maths(histogram,velocity,frequency polygon,frequency tables)

• Minimum is the beginning of the line and the lowest number from the data.
• Maximum is the end of the line and the highest number from the data.
• To work out cumulative frequency you must add the numbers.

  
• The graph must be shaped similar to an S

  
• In each group assume everyone spent the same midpoint
• Multiplay the frequency by the midpoint to find the estimated total group value
• To calculate the mean you must divide the total group value by the total frequency
• If the data is exact there is no midpoint

  
• If the data isn't exact (eg - 0<s≤6) there is a midpoint
• Frequency density is plotted on the y-axis
• Frequency is represented by the area of the base
• To work out the area of a triangle you 1/2 x base x perpendicular height
• 1/2 x 6cm x 8cm = 24cm

  
• To work out the area of a trapezium you 1/2 (a+b) x height
• 1/2 (30 + 10) x 20 = 400cm

  
• 8 x 7 = 56cm

  
• To work out the area of a rectangle multiply the base by the height
• What would the quartiles, IQR and range of this equation be

  14, 20, 25, 27, 27, 29, 35

  Q1 = 20, Q2 = 27, Q3 = 29, IQR = 29-20 = 9, Range = 35-14= 21
• What would be the cumulative frequency be for this table?

  Distance (d,km) | Frequency

  0 < d ≤ 1. |. 5

  1 < d ≤ 2. |. 12

  2 < d ≤ 3. |. 28

  3 < d ≤ 4. |. 20

  4 < d ≤ 5. |. 50

  The cumulative frequency will be

  5

  +12

  17

  +28

  45

  +20

  65

  +15

  80
• What would be the mid class value and total class value from this table

  Spent, s, (£). Frequency 0 < s ≤ 2 10 2 < s ≤ 4 20 4 < s ≤ 6. 25 6 < d ≤ 8. 10

  Mid class val. Total class val

  1. 10

  3. 60

  5. 125

  7. 70
• How do you work out the mean?

  Total class value

  ----------------

  Total frequency
• What would the mean to this equation be 265 ÷ 65

  £4.08
• How do you work out the modal class?

  You find the highest frequency on the table and then find the group it is in.

  Eg - if my highest frequency is 35 the modal class would be 20<t≤40
• To find how long the vehicle is accelerating you find the straight line that is going upwards until the line doesn't go the same way
• To find how long a vehicle is declarating you find the straight line going downwards until it finishes
• IQR is Q3 - Q1
• Range is the highest number - the smallest number