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Tape measure reading test

Read the pointer to the nearest sixteenth of an inch and pick the answer. Get it right and your streak climbs; miss and it resets. Turn on timed mode when you want the pressure.

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Cet exercice a besoin de JavaScript pour générer et corriger les questions. Activez-le pour vous exercer — l’explication ci-dessous fonctionne dans les deux cas.

How to read the tape

The graduations step down in length so you can read them at a glance. The longest, numbered line is the inch. Halfway between two inches is the next longest line — the half. Between those come the quarters, then the eighths, and the shortest lines of all are the sixteenths.

To read a mark, find the last whole-inch line before it and count the sixteenths past it. Say you land two inches and six little lines along: that is 2 and 6/16, and 6/16 reduces to 3/8, so the reading is 2 3/8". Reducing is just dividing top and bottom by the same number — 6/16, both divide by two, gives 3/8. Do that a hundred times here and it stops being arithmetic and becomes a look.

Three reads, worked

1. The pointer is on the long line halfway between 4 and 5

  1. Last whole inch before it: 4.
  2. The halfway line is the half mark. That is 8 sixteenths, which reduces to 1/2.
  3. 4 1/2". You never counted a single small line.

2. The pointer is three small lines past the 7

  1. Last whole inch: 7. Each small line is a sixteenth.
  2. Three past the inch: 3/16. Three is odd, so it does not reduce.
  3. 7 3/16".
The check

3/16 is a little under a quarter (4/16). So the pointer should be just short of the quarter line — the second-longest kind of mark after the half. If it is past the quarter line, you miscounted.

3. The pointer is one small line short of the 12

  1. Counting up from 11 would be fifteen lines. Do not. Count back from the 12 instead: one sixteenth short.
  2. A whole inch is 16/16, so one short is 15/16.
  3. 11 15/16". Reading back from the next inch is the trick for anything past the half.
The eight-mark habit

Past the half, count back from the next inch; before it, count up from the last one. You never count more than eight lines either way, and the reading-a-tape page turns that into the whole method.

The slips

  • Counting eighths as sixteenthsOn a tape graduated in eighths past the first foot, each small line is 2/16. Look at the finest mark before you count.
  • Reading from the wrong inchThe number is printed just past its line, not before it. The pointer on "the 7" is at 7, not 6 15/16.
  • Not reducing10/16 is 5/8. 12/16 is 3/4. The buttons in the drill are reduced, so reduce before you look for your answer.

Questions fréquentes

How do I read a tape measure to 1/16 of an inch?

Find the last whole-inch line before the mark, then count the small graduations past it. The very shortest lines are sixteenths, so four of them make a quarter and eight make a half. Read the whole inches, add the sixteenths, and reduce the fraction: 8/16 is a half, 12/16 is three-quarters.

Which lines are which on the tape?

They step down in length. The longest line with a number is the inch. The next longest, halfway between, is the half. The quarters are shorter again, the eighths shorter still, and the shortest lines of all are the sixteenths. The length of the line tells you the fraction without counting every tick.

Why practise this?

Because reading a tape fast and right is a first-year skill everyone is quietly expected to already have, and a misread of a sixteenth compounds over a long run. A few minutes of drilling turns hesitation into a glance.

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