Introduction: How to Measure Circles With a Ruler

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have you ever been confused on how to measure circles, have you ever wandered, can you measure a circle with a straight ruler? Well, I am here to tell you, you can! All it takes is a little math, don't leave yet, its just multiplication, you can do it.

Supplies

flexible measuring tape

ruler

printer

calculator(or a piece of paper)

pen

Step 1: Print

print this page(ctrl + p ). Go into print settings, set layout to landscape, turn off margins, and print template. Then lay flat on table.

click here

Step 2: Terminoligy

diameter- The length across the circle(though the center)

radius- half the diameter

circumference- distance around the circle(if you took the circle and laid it out flat)

last but not least pi- the number that is used to multiply to find out the circumference from the diameter, or radius.

Step 3: Measure

Now, take your flexible measuring tape and measure the circumference each circle, then write down the measurements by the circles. Next, measure across the center with a ruler and record each size.

Step 4: Multiply

take the diameter(distance across the center ) and multiply by 3.14159265.......

OK you don't have to multiply by all the digits of pi, pi is an irrational number, it never ends and never repeats, so people usually just round to 3.14 and call that close enough. so, multiply each diameter by 3.14 and write down the results.

Step 5: Compare

are your measurements the same, if so, good job,you have learned how to use pi, you have learned what circumference means, you have learned what diameter means and you now can measure circles with a ruler!

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