First choose the starting endpoint
Perceptle Friday fraction helper
A fraction above one goes beyond the other end. See where it lands from the left or the right, then try placing it yourself.
Drag the round marker. The bold segment from 0 to 1 is the original line; the lighter extensions are additional space. Keyboard arrows move 0.01 line lengths; Shift + arrow moves 0.1.
Where is 3/2 of a line?
3/2 is one and a half times the original line length. From the left, travel one full length to the right endpoint, then another half-length to coordinate 1.5. From the right, travel left by 1.5 lengths: the target ends at −0.5, half a line length beyond the left endpoint.
| Fraction | Percentage | From left | From right |
|---|---|---|---|
| 3/2 | 150% | 1.5 | −0.5 |
| 5/4 | 125% | 1.25 | −0.25 |
| 8/5 | 160% | 1.6 | −0.6 |
| 2/3 | 66⅔% | 0.666… | 0.333… |
Which line length goes into the score?
Always the original segment between the two endpoints. If your point misses by 0.05 of that original length, the error remains 5% even when the drawing includes extra space. Friday’s tolerance is 10% of the original line; Normal uses 5%.
Why does the starting side matter?
All displayed coordinates use left = 0 and right = 1. A left-origin fraction r lands at r. A right-origin fraction lands at 1 − r. Check the requested origin before estimating; a point at 25% from the right is 75% from the left.
Use the Split guide for mental landmarks and common mistakes, or compare Normal and Friday in the error calculator.