# Math

 Adding Decimals   7.2 +9.5 _____ 16.70 Make sure decimals are lined up Subtracting Decimals   5.6 - 3.5 ____   2.1 Make sure decimals are lined up Finding GCF (Greatest Common Factor) 12, 18 1; 2; 3; 4; 6 1; 2; 3; 6 Find the largest number that will go in each number equally Find LCM ( lowest common multiple) 5; 6; 15 30 the lowest number that each will go into equally Adding Unlike Fractions 1/3 + 1/6 Find the lowest common demoninator which is 6 in this case. 1/3 becomes 2/6 (6/3=2 & 2*1=2) 1/6 becomes 1/6 (6/6=1 & 1*1=1)   2/6 +1/6 ____ 3/6 and reduces to 1/2 Subtracting Unlike Fractions 3/4 - 1/5 Find the LCD (lowest common denominator) which is 20 3/4 becomes 15/20 (20/4=5 & 5*3=15) 1/5 becomes 4/20 (20/5=4 & 1*4=4)   15/20 -  4/20 ______   11/20 Estimating Product (using rounding)    8.7 ≈ 9 x 2.8 ≈ 3 ____________            27 Examples of rounding: 91≈90 34≈30 598 ≈600 143≈140 255≈260 704≈700 705≈710 Multiply Decimals 0.83 x  4 _____ 3.32  multiply as whole number and count the same number of decimal places.   14.2 x     3 _____ 42.6 0.018 x   2 _____ 0.036 Multiply Decimals by Decimals 4.2 x 6.7    4.2 x 6.7 ____    294  multiply as if whole numbers  252 ____ 28.14 count same number of decimal places       1.4 x 0.067 ________     0268   0067 ______  0.0938 Divide.  Round to the nearest tenth if necessary 6.8 ÷ 2  line the decimal point in the answer   _3.4__ 2  6.8   - 6   ____        8       -8 _______         0 *********************************** 7.70 ÷14     _0.55 14  7.70      -70     ____         70       - 70     _____           0 *********************************** 6.74 ÷ 3      2. 246      3   6.74     -6 ________       07       -6 _______         14        -12 ________            20 anex a zero           -18 __________              2  The remainder will never be a 0 Find Each Quotient 81.7 ÷ 100 = .817 100 has two zeros...so move decimal over two places to the left .48 ÷ 1000 = .00048 1000 has three zeros..so move decimal over three places to the left  Find each Product .35 x 100 = 35 100 has two zeros..so move decimal over two places to the right 8.5 x 1000 = 8500 1000 has three zeros..so move decimal over three places to the right Write each Product using an Exponent 6x6x6x6=64 Product as a Power 52 = 5x5 = 25  Power as Produck of same factor - Then find Value 1.53 = 1.5 x 1.5 x 1.5 = 3.375 1.5 x 1.5 = 2.25 x 1.5 = 3.375 Dividing by Decimals 1.71 ÷ 0.9There is one place after the decimal 0.9 so move the other number over by one place.      1.99   17.1-     9_______       81-      81 What is a fraction? A number that names part of a whole or group Numerator si the top number Denominator is the bottom number Reducing Fractions Two Rules: 1.  You can divide top & bottome by any number as long as you use the same number for both. 2.  You need to get both numbers as small as possible 100 ÷ 100 = 1 200 ÷ 100 = 2  8 ÷ 8 = 1  24 ÷8 = 3  4 ÷ 2 = 2 10 ÷ 2 = 5 Part of a number Find 5/7 of 14 14 ÷ 7 = 2 then 2 x 5 = 10 So 5/7 of 14 is 10 Find the reciprocal 2/3 = 3/2 simply turn the fraction up side down Divide.  Write in simplest form (making the second fraction into a reciprocal) 2 ÷ 1/3 = 2/1 x 3/1 = 6/1 = 6 ************************** 5 ÷ 2/7=5/1 x 7/2 = 35/2 = 17 1/2 **************************1/8 ÷ 1/2=1/8 x 2/1 = 2/8 or 1/4 *************************5 1/2 ÷ 2 = 11/2 x 1/2 = 11/4 = 2 3/4 AuthorAudreyHess ID173307 Card SetMath DescriptionBlakes - 6th grade math Updated2012-10-18T18:38:37Z Show Answers