The table shows the numbers of cases of Corona Virus registered in Uganda between March, 2020 and June, 2021. Draw a frequency distribution table, a graph of cumulative frequencies, and estimate the median.

Mathematics
The table shows the numbers of cases of Corona Virus registered in Uganda between March, 2020 and June, 2021. Draw a frequency distribution table, a graph of cumulative frequencies, and estimate the median.

ScanSolve AI Answer

Answer

26

Step 1: Determine the total number of cases.
Add the frequencies:
14+15+20+14+9+5+2+1+1=8114 + 15 + 20 + 14 + 9 + 5 + 2 + 1 + 1 = 81
Total cases, N=81N = 81.

Step 2: Identify the median position.
The median is the N+12\frac{N+1}{2}th value:
81+12=41\frac{81 + 1}{2} = 41
The 41st case.

Step 3: Construct the cumulative frequency (cf) table using upper class boundaries.
Classes: 090-9, 101910-19, 202920-29, 303930-39, 404940-49, 505950-59, 606960-69, 707970-79, 80+80+.
Upper boundaries: 1010, 2020, 3030, 4040, 5050, 6060, 7070, 8080, 9090.

Classfcf091414101915292029204930391463404997250595776069279707918080+181\begin{array}{c|c|c} Class & f & cf \\ \hline 0{-}9 & 14 & 14 \\ 10{-}19 & 15 & 29 \\ 20{-}29 & 20 & 49 \\ 30{-}39 & 14 & 63 \\ 40{-}49 & 9 & 72 \\ 50{-}59 & 5 & 77 \\ 60{-}69 & 2 & 79 \\ 70{-}79 & 1 & 80 \\ 80+ & 1 & 81 \\ \end{array}

Step 4: Draw the cumulative frequency polygon (ogive).
Plot points: (10,14)(10,14), (20,29)(20,29), (30,49)(30,49), (40,63)(40,63), (50,72)(50,72), (60,77)(60,77), (70,79)(70,79), (80,80)(80,80), (90,81)(90,81).
Join with straight lines.

Step 5: Locate the median on the graph.
Draw horizontal line at cf =41= 41.
It intersects the line segment from (20,29)(20, 29) to (30,49)(30, 49).

Step 6: Calculate the median value.
Formula for intersection:
x=L+Mcfprevcfcfprev×wx = L + \frac{M - cf_{prev}}{ cf - cf_{prev} } \times w
where L=20L = 20 (upper boundary of previous class),
M=41M = 41 (median position),
cfprev=29\text{cf}_{prev} = 29,
cfcfprev=4929=20\text{cf} - cf_{prev} = 49 - 29 = 20,
w=3020=10w = 30 - 20 = 10 (class width).

Substitute:
x=20+412920×10x = 20 + \frac{41 - 29}{20} \times 10
x=20+1220×10x = 20 + \frac{12}{20} \times 10
x=20+0.6×10x = 20 + 0.6 \times 10
x=20+6=26x = 20 + 6 = 26

(c) Explanation: The ogive is plotted with cumulative frequencies against upper class boundaries. The horizontal line at cf =41= 41 intersects the ogive between upper boundaries 2020 and 3030. The x-coordinate of the intersection gives the estimated median of 2626 cases.

26

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Quick Answer

Determine the total number of cases. Add the frequencies: 14 + 15 + 20 + 14 + 9 + 5 + 2 + 1 + 1 = 81 Total cases, N = 81.

The table shows the numbers of cases of Corona Virus registered in Uganda between March, 2020 and June, 2021. Draw a frequency distribution table, a graph of cumulative frequencies, and estimate the median.
Mathematics

This mathematics problem involves applying core mathematical principles and formulas. Below you will find a complete step-by-step solution with detailed explanations for each step, helping you understand not just the answer but the method behind it.

ScanSolve AI Answer
Step 1: Determine the total number of cases. Add the frequencies: 14 + 15 + 20 + 14 + 9 + 5 + 2 + 1 + 1 = 81 Total cases, N = 81. Step 2: Identify the median position. The median is the (N+1)/(2)th value: (81 + 1)/(2) = 41 The 41st case. Step 3: Construct the cumulative frequency (cf) table using upper class boundaries. Classes: 0-9, 10-19, 20-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80+. Upper boundaries: 10, 20, 30, 40, 50, 60, 70, 80, 90. c|c|c Class & f & cf \\ 0-9 & 14 & 14 \\ 10-19 & 15 & 29 \\ 20-29 & 20 & 49 \\ 30-39 & 14 & 63 \\ 40-49 & 9 & 72 \\ 50-59 & 5 & 77 \\ 60-69 & 2 & 79 \\ 70-79 & 1 & 80 \\ 80+ & 1 & 81 \\ Step 4: Draw the cumulative frequency polygon (ogive). Plot points: (10,14), (20,29), (30,49), (40,63), (50,72), (60,77), (70,79), (80,80), (90,81). Join with straight lines. Step 5: Locate the median on the graph. Draw horizontal line at cf = 41. It intersects the line segment from (20, 29) to (30, 49). Step 6: Calculate the median value. Formula for intersection: x = L + M - cf_prev cf - cf_prev × w where L = 20 (upper boundary of previous class), M = 41 (median position), cf_prev = 29, cf - cf_prev = 49 - 29 = 20, w = 30 - 20 = 10 (class width). Substitute: x = 20 + (41 - 29)/(20) × 10 x = 20 + (12)/(20) × 10 x = 20 + 0.6 × 10 x = 20 + 6 = 26 (c) Explanation: The ogive is plotted with cumulative frequencies against upper class boundaries. The horizontal line at cf = 41 intersects the ogive between upper boundaries 20 and 30. The x-coordinate of the intersection gives the estimated median of 26 cases. 26