**MEASURING UNITS**

**Measurement is a very important part of everyday life. We measure all sorts of things. Here are just a few of them:**

**• Size and distance: How tall you are;****how far away your school is. ****Weight: How much do you weigh; how****heavy is your backpack. ****Area: How large is your apartment. ****Volume: How much water is in your bathtub. ****Time: How long does it take you to read this paragraph: how old you are.**

**Two Different Systems**

There are two main systems of measurement in the world today. In America, we use the English system, which involves units such as inches, feet, yards, and miles for measuring lengths; ounces, pounds, and tons for measuring weights; and cups, pints, quarts, and gallons for measuring liquid volumes

Most of the rest of the world (including more and more, England) uses the metric system. In this system, lengths are measured in millimeters, centimeters, meters, and kilo. Meters; weights in grams and kilograms; and liquid volumes in milliliters and liters. The metric system is based on the base of 10.

**A Metric Mnemonic**

A mnemonic is a memory trick to help you remember tricky information. The metric system is based on factors of 10, but the words used to represent each multiplication (or division) by 10 are easy to confuse. Here is a mnemonic device to remember the order of the prefixes in the metric system. Kilo Hecto Deka → unit 4 Deci Centi – Milli

Each arrow represents a factor of 10. When you move to the right, the measure gets smaller (divide by 10) for each arrow. When you move to the left, the measure gets larger (multiply by 10).

**I Here’s a story to help you remember the order of the names of the prefixes:**

During medieval times, Kings considered themselves to be above all other Humans, and Humans considered themselves to be above the Dragons. These are the mighty and all are above the basic unit. Below the basic unit are Dogs, which considered themselves to be above Cats, which considered themselves to be above Mice.

**NOT BY A LONG SHOT**

How do we measure length and distance? With inches, feet, yards, miles or with millimeters, centimeters, meters, and kilometers. Here is the conversion table:

1 mile = 5,280 feet 1 yard = 3 feet 1 foot = 12 inches

1 kilometer = 1,000 meters 1 meter = 100 centimeters 1 centimeter = 10 millimeters

1 mile = 1.61 kilometers 1 foot = 0.3048 meters 1 inch = 2.54 centimeters

1 kilometer = 0.6214 miles 1 meter = 39.37 inches 1 millimeter = 0.0394 inches

**A WEIGHTY MATTER**

It helps to know how much things weigh. We measure candy in ounces, fruit and vegetables in pounds, and elephants in tons. Here are the conversion tables for metric and English weight measurements.

1 ton = 2,000 pounds 1 pound = 16 ounces

1 kilogram = 1,000 grams 1 gram = 1,000 milligrams

1 ton = 1,016.05 kilograms 1 pound = 0.45 kilograms 1 ounce = 28.4 grams

1 kilogram = 2.2 pounds 1 gram = 0.035 ounces

**STACKING UP ZEROS**

Why is the metric system based on 10? Because our entire number the system is built on multiples of 10. Think of it this way: You’ve got 1, 2, 3, 4, 5, 6, 7, 8, 9, and then you go back to 1 and just add a 0 to it-10. Add another 0. and you get 100. How many zeros can you keep on stacking? Take a look here:

**NUMBER OF ZEROS** **WHAT YOU GET**

0……………………………………………one

1……………………………………………ten

2……………………………………………hundred

3……………………………………………thousand

4……………………………………………ten thousand

5…………………………………………… hundred thousand

6……………………………………………million

7……………………………………………ten million

8……………………………………………hundred million

9…………………………………………… billion