The table shows the weekly wages of 30 workers in a factory. By forming the frequency table using the intervals 30 to 39, 40 to 49, 50 to 59, 60 to 69, 70 to 79, 80 to 89, and 90 to 99, find which interval has the highest frequency.
We were asked in the question to form a frequency table with groups from 30 to 39 up to 90 to 99. There were eight workers whose wage was between 30 and 39. Seven of the workers had a wage between 40 and 49. Three out of the 30 workers had a wage between 50 and 59. There was one worker whose wage was between 60 and 69. Four of the workers had a wage between 70 and 79. There were two workers that had a wage between 80 and 89. And four of the workers had a wage between 90 and 99. It’s important to note that there was also one worker who had a wage of 100.
The question asked us to work out which interval had the highest frequency. Well, the highest frequency in the table was eight. This corresponded to a wage of between 30 and 39.
Therefore, the interval that had the highest frequency is 30 to 39. This is also known as the modal group.