Gr 11 Math Ch 11: Ogives

What is the formula to calculate the cumulative frequency up to the i-th interval?

CF_i = ∑(j=1)^i f_j (correct)

CF_i = ∑(i=1)^j f_j

CF_i = ∑(j=1)^i f_j^2

CF_i = ∑(j=1)^i (f_j - 1)

What are the points used to plot an ogive?

(x_0, CF_1), (x_1, CF_2), (x_2, CF_3), …, (x_i, CF_i)

(x_0, 1), (x_1, CF_1), (x_2, CF_2), …, (x_i, CF_i)

(x_0, 0), (x_1, CF_1), (x_2, CF_2), …, (x_i, CF_i) (correct)

(x_0, CF_0), (x_1, CF_1), (x_2, CF_2), …, (x_i, CF_i)

What is the first step in constructing an ogive?

Create a cumulative frequency table from the frequency table. (correct)

Plot points using the upper limits of intervals and their corresponding cumulative frequencies.

Identify the median of the data set.

Connect the points with straight lines.

What percentile is the median equivalent to?

50th percentile Signup and view all the answers

What is the formula to calculate the k-th percentile?

P_k = (k/100) × N Signup and view all the answers

What is the purpose of an ogive?

To find the median, quartiles, and percentiles of a data set. Signup and view all the answers

What is the cumulative frequency of the 3rd interval, given the frequencies of the first three intervals are 5, 8, and 12?

25 Signup and view all the answers

In an ogive, what is the y-axis typically represented by?

Cumulative frequency of each interval Signup and view all the answers

What is the purpose of finding the median using an ogive?

To identify the middle value of the data Signup and view all the answers

How do you find the third quartile (Q3) using an ogive?

Locate the 75th percentile on the cumulative frequency axis Signup and view all the answers

What is the interpretation of the 75th percentile?

75% of the data points are below this value Signup and view all the answers

What is the advantage of using an ogive over a frequency table?

It provides a visual representation of the cumulative frequency Signup and view all the answers

A dataset has 30 observations. What is the cumulative frequency at the 60th percentile?

20 Signup and view all the answers

An ogive is used to find the median of a dataset. If the median is 25, what is the corresponding cumulative frequency?

20 Signup and view all the answers

A frequency distribution has a total of 50 observations. What is the cumulative frequency at the 30th percentile?

15 Signup and view all the answers

An ogive is used to find the first quartile of a dataset. If the first quartile is 10, what is the corresponding cumulative frequency?

7.5 Signup and view all the answers

A dataset has 40 observations. What is the cumulative frequency at the 20th percentile?

8 Signup and view all the answers

An ogive is used to find the third quartile of a dataset. If the third quartile is 30, what is the corresponding cumulative frequency?