Question

The cummulative frequency of a class is the frequency obtained by adding the frequencies of all the classes preceding the given class . True or false​

Answer 1

Step-by-step explanation:

The cumulative frequency gives the number that falls into the current class interval or any class interval that comes before it. You could think of it as ‘the number so far’ function. To find the cumulative frequency for a class, take the number in the current class and add on the previous cumulative frequency for the class below, for example, for 1900–2000 we have a frequency of 92. The cumulative frequency for 1800–1900 is 859. Add 859 + 92 to get the cumulative frequency of 951. That is, 951 light bulbs in the sample have a lifetime below 2000 h. Notice that the cumulative frequency of the final class must equal the total number in the sample. This is because the final class must include the maximum value in the sample and all the others have lifetimes less than this. it is false