We’ll discuss how to use here Line markings.

We know that data is a collection of information. When the data is large, counting may not be easy. So we use counters. Tally Marks is the quick way to record the given dates by grouping them into groups of five. The first four tallies are marked vertically and the fifth tally in a pile is marked diagonally across the four tallies.

To count the number of times a value of the variable is displayed in a data collection, we use the dash character (/). The line marking therefore represents the frequency.

Note the line markings and the corresponding frequencies:

Example:

(i) Write the tick marks for a frequency of 22.

(ii) What frequency corresponds to the counters?

Solution:

(I)

(ii) 16 (Da 5 + 5 + 5 + 1 = 16)

Problems with Tally Marks:

1. The weights (in kg) of the school teachers are recorded as shown below.

60, 65, 63, 70, 65, 62, 65, 63, 64, 60, 68, 58, 62, 65, 63, 65, 64, 60, 62, 63.

If you want the data collection to be grouped into class intervals 56-59, 59-62, 62-65, 65-68, 68-71, write the tick marks for the frequency of variation 65 and the class interval 62-65.

(Since only 62, 62, 62, 63, 63, 63, 63, 64, 64 fall into this class)

2. The weights (in kg) of the school teachers are recorded as shown below.

60, 65, 63, 70, 65, 62, 65, 63, 64, 60, 68, 58, 62, 65, 63, 65, 64, 60, 62, 63.

If you want data collection to be grouped into class intervals 56-59, 60-63, 64-67, 68-71, write the tick marks for the class 60-63 frequency.

(Since only 60, 60, 60, 62, 62, 62, 63, 63, 63, 63 fall into this class)

1. 20 students gave their choice of preferred taste of soft drinks as follows. Line up the information provided.

 Orange, Cola, Lemon, Lemon, Cola, Cola, Mango, Mango, Cola, Orange, Orange, Orange, Mango, Cola, Cola, Cola, Cola, Orange, Lemon, Orange.

Number of orange flavor: 6

Number of Cola Flavors: 8

Number of lemon flavor: 3

Number of mango flavors: 3

2. Note the table provided. It shows the different shapes that students use to decorate the class blackboard. Present the data using a tally chart.