This page will help you to review some of the vocabulary words or main ideas that we have covered. Use it to reinforce a concept or as a study guide.

## Math:

**Mean**: (average) add the data and then divide the sum by how many numbers there were.

**Median**: put the numbers in order from least to greatest and them cross off from each side until you find the middle number. If two numbers end up in the middle…add them and them divide by two.

**Mode**: the number that appears the most

**Numerical patterns**: a list of numbers that occur in a predictable way.

3, 7, 15, 31, ___, ___ (ans: pattern: *2+1)

**Variable**: a letter that represents a number that varies

(ex: a+2…if a is a “4” then the equation = 6

BUT if ‘a’ is a “9” then the equation = 11)

**Constant**: a quantity that does not change

(ex: a 5 is always = 5)

**Expression**: is a phrase in math the uses constants and variables and different operations symbols.

(ex: 5*4+a)

**EXPONENTS**: a small number placed in the upper corner of a number (called the base)

this small number tells you how many times to multiply the base number.

(ex: 3^{3}= 3 x 3 x 3 which is equal to 27)

DO NOT add 3+3+3 ALWAYS multiply the base as many times as the exponent

**Equation**: a math sentence that uses an = sign

(ex: 5 + 7 = 12….or r + 10 = 30, r=20)

**Solving equations**: isolate the variable by removing all numbers from it’s side of the equal sign EX:

w + 12.3 = 42.5

subtract 12.3 from each side of the equation

w + 12.3 – 12.3 = 42.5 -12.3

w + 0 = 30.2

w= 30.2

**Improper Fractions**: fractions that have the top number (numerator) larger

than the bottom number (denominator) Example:

Divide the numerator by the denominator

and use any remainder over the same denominator.

57 divided by 25 = 2 and 7/25

**Metric system**:

**Meters**: to measure length**Liters**: to measure liquids**Grams**: to measure weight

**A meter** is a little longer than a yard stick. **A liter** is about two water bottles. **A gram** is about the weight of a raisin.

using the prefix **Kilo** means **1000**…therefore a *Kilometer* is 1000 meters ( or a little over 1000 yard sticks)

using the prefix **Hecto** means **100**…therefore a *Hectometer* is 100 meters.

using the prefix **Deka** means **10** ….therefore a *Dekameter* is 10 meters.

using the prefix **Deci** means **1 tenth**… therefore a *Decimeter *means you broke up the meter stick into 10 pieces and you have 1 of the pieces (there are 9 left)

using the prefix **Centi** means **1 hundredths**… therefore a *Centimeter* means you broke up the meter stick into 100 pieces; you have 1of the pieces (there are 99 left)

using the prefix **Milli** means **1 thousandths**….therefore a *Millimeter* means you broke up the meter stick into 1000 pieces; you have 1 of the pieces (there are 999 left)

**GEOMETRY Formulas**:

**POLYGON**is any shape that is made with straight lines and has no openings.**PERIMETER**: adding up all the sides of the polygon together**AREA**: Determining how many squares would fit into the shape…this is a little trickier! :)**SQUARE**or**RECTANGLE**or**PARALLELOGRAM**: multiply the base number by the height number. Be careful… the height number is not the side number on a parallelogram!**TRIANGE**: a triangle is one half of a rectangle or square…so the formula is BASE multiplied by HEIGHT (not side) divided by two.**CIRCLE**: the edge is called**circumference**. to find the circumference multiply the diameter (the distance across the circle) by 3.14 or pi.**VOLUME**: to find volume of a 3 dimensional shape you must multiply the base times the height times the width. The answer must be stated in cubic terms. example: 2ft x 4ft x 6 ft = 48 cubic feet