### CFA Practice Question

There are 410 practice questions for this study session.

### CFA Practice Question

When grouping data with the purpose of constructing a frequency distribution, the suggested number of equal-sized classes for a data set with 210 observations is ______.
A. 6
B. 7
C. 8
Explanation: When constructing a frequency distribution, you may approximate the number of classes of the distribution (k) with the smallest integer (k) such that: 2k >= Number of observations

Therefore, we are looking for the smallest integer k, such that: 2k >= 210. We obtain k=8.

User Comment
sonderfall 2^k = 210
k x log 2 = log 210
k = log 210 / log 2
k = 7.714
Nuta I didn't understand: why 2^k? Could somebody explain? thanks!
kellyyang I don't understand this questions either! can someone can explain a easy way to answer this problem.
shiva5555 What is constructing a frequency distribution?
poomie83 frequency distribution tables or histograms are just summaries of the calculated data. It is supposed to be an easier way to interpret the data.

2^k is the formula used to equate the intervals back to the observations. You need to learn it just like the 104 other formulae
bruffel some of these questions definitely will not appear on the actual exam... this is one of those
e22205 was I doing something wrong? I keep getting 2^8 = 256. And then I noticed it's >= 210, so never mind.
navarro Can someone please explain me this? I'm stuck with this one. Thank you in advance.
Ladygaga @Nuta: for example, you have 3 responses about fruits, you can ask 2 question to classify them: Do you like apple and do you like bananas. The answer will definitely fall into either YY, YN, NY, NN. This makes sure that you have a class for each possible response
yangv Why 2??