Explanation of the Project
Our class has been engaged in a data gathering unit in math. In one activity we looked at the types of fingerprints each of us has. We noticed that of the three basic types of prints (loop, arch and whorl), a large majority of our class had loop prints. We discussed whether this would be true in the larger population. Many students thought that it was likely only a coincidence that so many of us had loop prints, but other students thought that perhaps our class was similar to the rest of the population. So out of any 20 people surveyed, most (70% or so) would have loop prints.
Loop Our Class By Percent Other Classes By Percent 14 70 41 68
Whorl 3 15 8 13
Arch 3 15 11 18
Gathering Print Samples
Gathering print samples is a relatively simple process. 1. Give each student a 2-3 cm long strip of clear tape. 2. Have each student rub a pencil on paper, then press their right index finger into the pencil rubbing. 3. Each student then presses their smudged finger hard onto the sticky side of the clear tape. This will move the finger smudge onto the tape. 4. The tape is then stuck down onto white paper for analysis. A magnifying lens and the picture samples below will help you in identifying the type of prints.
Analyzing Prints
Although there are a number of subtle variations of the three basic types of prints, for our purposes we will restrict ourselves to the following types:
Arch
Ridges in an arch pattern progressively build up a mound above a fairly horizontal set of lower ridges. The arch pattern is the only pattern without a "delta" or triangular pattern made of ridges forming a triangle around a point.
Whorl
Ridges form a circular pattern completely around a central point or short line. Typically two deltas will be noticed below and to the outside of the whorl.
Loop
Ridges form a tall narrow loop coming in from either the right or the left side of the print. Loops are characterized as having one delta pattern below and to the side opposite from which the loop is formed. Sometimes two loops will appear on the same print.