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# 7.1

### Unit 1 Test Review

Term | Definition |
---|---|

ratio | a comparison of two quantities using division, which can be written 3 ways ex. 5/7, 5:7, 5 to 7 |

rate | a ratio that compares two quantities measured in different units ex. 20 miles in 2 hours |

proportion | an equation that states that two ratios are equal to each other 1/4 = 3/12 |

equivalent Ratios | ratios that have the same value 1/2 = 2/4 |

cross products | the product of numbers on the diagonal when comparing two ratios are equal |

scaling up | creating an equivalent ratio by multiplying the top and bottom of a fraction by the same number |

scaling down | creating an equivalent ratio by dividing the top and bottom of a fraction by the same number |

how to find equivalent ratios | 1. divide each fraction and see which ones are equal as decimals OR 2. Scale up or scale down OR 3. use cross products to see if they are equal |

How to solve a proportion with a missing value | 1. use cross products to write and solve an equation OR 2. scale up or scale down |

unit rate | a rate that has a denominator of 1 20 miles per (1) hour |

how to calculate a unit rate | divide the numerator by the denominator 20 miles/2 hours = 10 miles per hour |

multiply fractions | Multiply the tops, then multiply the bottoms, always reduce your answer |

Multiply Mixed Numbers | Change them into improper Fractions, then use the rules for Multiplying Fractions |

divide fractions | change into improper fractions, then multiply by the reciprocal (keep, change, flip) |

solve a word problem with proportions | 1. read the problem carefully 2. set up a proportion carefully- lining up like units and making the unknown x 3. use cross products to write and solve an equation to find your missing infomation |

how to calculate best buy | divide price by number of both items and compare to see which unit rate is lower |

find the missing side of a similar figure | 1. write a proportion, making sure to line up information correctly 2. use cross products to write and solve and equation for the missing side OR 1. Scale up or scale down |

Use a proportion to solve a scale problem with missing information | 1. write a proprotion (using the scale as the first rate), making sure to line up information correctly 2. use cross products to write and solve and equation for the missing information OR 1. Scale up or down if given a scale with 1 |

Perimeter of a rectangle | add all sides together (remember there are 4 sides) |

perimeter of a rectangle under a scale factor | multiplied by the scale factor |

area of a rectangle | A=lw units are squared |

area of a rectangle under a scale factor | multiplied by the scale factor squared |

proportional | when two quantities have a constant rate or COP |

non-proportional | when two quantities DO NOT have a constant rate or COP |

constant of proportionality | the constant ratio between two quantities, found by dividing y by x |

proportions in tables | divide y/x and see if they are all the same |

y = kx | the formula used for proportional relationships, where k = the constant rate (COP) |

origin | ( 0 , 0 ) |

proportions in graphs | 1. Straight line (linear) 2. Goes through origin |

( 1 , r ) | the ordered pair for unit rate |

describe a point on a graph based on the situation | use the labels to identify which each point refers to Ex. (1 , 30) = 1 hour for 30 miles or 30 miles per hour |