APPLIED  MATH I

Below you will find information on the topics we cover in class.  Use the information on these pages to help you review the topics.

Ratios      Ratios are a way of comparing two quanities using division. To compare the number of apples, 25 to the number of pears, 20 in a basket you could write a fraction.     apples               25                                              pears                20 Or you could write the ratio (comparison)  using a colon ( : )                 apples : pears                or              25 : 20 Or you could write the ratio (comparison)  using the word " to "                apples to pears                or              25  to 20 How do I know which number to write first?      The number or word mentioned first, before the word to, is the one that goes in the numerator (on top) of our ratio. Most of our ratios will be written as fractions.

Proportions       Proportions are two or more equivalent (equal) ratios.    Example  1 / 2   =  2 / 4  = 3 / 6 = 4 / 8 In real life we can use proportions to solve a wide variety of problems.        If I know that 3 socks cost me $4.05 how much will 5 socks cost        I need to set up a ratio of   socks to cost,   3 / 4.05,  5/ ?                                                                   socks      3    =  5                                                                    cost         4.05        ?         We will use  y  for our unknown cost ?          Next I need to cross multiply                   3 (y) =  4.05 (5)          4.05 x 5 = 20.25                                         3 (y) =  20.25                    Divide both sides by 3                             3 (y) =   20.25                                                                             3              3           y the cost of 5 socks is                                 y   =    6.75

PRACTICE PROBLEMS Go to the Funbrain site and use the practice problems below to practice Multiplying and Dividing Integers.  Take the practice quiz as many times as you like.  It is not for a grade but to practice for your test.  Our secret word is math 01 Don't forget there is a space between the h and the 0.                   Proportions Practice

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APPLIED MATH I

PRACTICE PROBLEMS Go to the  Quia Proportions (Equivalent Ratios) game and practice the rules for solving proportions.  This is a good way to study for your test and learn the rules.  MAKE SURE YOU PLAY ATLEAST 4 ROUNDS OF THE MATCHING GAME.

PROPORTIONS TEST Go to the Funbrain site and take the  PROPORTIONS TEST . Make sure you use the practice above first!  Our secret word is math 01 Don't forget there is a space between the h and the 0. Be sure to enter your first and last name.                PROPORTIONS TEST