How to calculate function points

Question

This is a matter of theoretical computation. I came across a question as shown below:

Consider a project with the following functional units:

• Number of user inputs = 50
• Number of user outputs = 40
• Number of user queries = 35
• Number of user files = 06
• Number of external interfaces = 04

Assuming that the correction factors of the entire complexity and the weighting factors are average, the points of the function for the project will be:

Answer: 672. How is this calculated?

Answer 1

1. Typical average difficulties:

AVERAGE difficulty weights = {4, 5, 4, 10, 7} for 5 difficulties, respectively.

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2. Typical weight characteristics:

AVERAGE characteristic weight = 3.

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3. Function point = FP = UPF x VAF

UFP = Sum of all difficulties, i.e. 5 parameters asked in the question,
VAF = Value Added Ratio, i.e. 0.65 + (0.01 * TDI) ,
TDI = Total impact of 14 overall system characteristics.

Thus, the functional points can be calculated as:

 = (200 + 200 + 140 + 60 + 28) x (0.65 + (.01 x (14 x 3)) = 628 x (0.65 + 0.42) = 628 x (1.07) = 672 

Thus, the functional points for the project will be 672 .

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Design this article for a detailed transition to the calculation of functional points.