Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Chapter 7 lesson 1 0011 0010 1010 1101 0001 0100 1011 1 cjm12/28/2012 2 4 Multiplying whole numbers and fractions 4/5 of 20 is the same as 4/5 x 20 or 20 x 4/5 0011 0010 1010 1101 0001 0100 1011 • How • Using 20 counters, divide them into 5 groups. • Circle 4 groups (4/5) • How many counters are circled? 16 many are in each group? 2 14 4 4/5 x 20=16 Example (pg 292) 2/3 of 12 or 2/3 x 12 • Using 12 counters, 0011 0010 1010 1101 0001 0100 1011 divide them into 3 groups. (Hint: the denominator tells you how many groups; the numerator tells you how many to circle.) • Circle 2 groups. • How many counters are circled? 8 1 2 4 2/3 x 20= 8 Try this! Draw an array for the problem on page 292. XXXX XXXX XXXX XXXX 0011 0010 1010 1101 0001 0100 1011 ¾ x 16= How many groups should you draw? 4 How many counters did you circle? 2 112 4 How many So, 12 of Susan’s stamps groups shouldare from the United States you circle? 3 and 4 stamps are not. Share & Show 8 rows 0011 0010 1010 1101 0001 0100 1011 7/8 x 16= 14 How many rows of counters? How many are in each row? Circle ____ rows to solve. How many counters are circle? 2 7 14 1 2 4 Use a model to solve. 0011 0010 1010 1101 0001 0100 1011 2. 2/3 x 18= 3. 2/5 x 15= 4. 2/3 x 6= 1 2 4 Other methods to solve these problems: 0011 0010 1010 1101 0001 0100 1011 5. 5/8 x 24= 15 5 X 24 = 5 x 24= 120 • Multiplication: 8 8 The 8 slides over. 120 is an improper fraction: 8 divide to simplify. 15 x 8 = 120 1 2 4 15 8) 120 -120 0 Important!! Multiply the numerator by the whole number. Other methods to solve these problems: 0011 0010 1010 1101 0001 0100 1011 • Division, then multiplication: 8 ÷8=1 1 3 5 x 24= 8 1. Look at the denominator and the whole number. Is there a number that will go into both of them? 24÷8=3 15 1 2 Both numbers (24 & 8) can be divided by 8. (Reduce by 8) 4 2. Now with 1 on the bottom, it is just 5 x 3= 15.