6-5 Multiplying and Dividing Decimals by PRmxmv

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									6-5 Multiplying and Dividing
         Decimals
   Objective: Multiply and divide
             decimals.
                 5-Minute Check
1. Name the multiplicative inverse of 12/5.
                 5-Minute Check
1. Name the multiplicative inverse of 12/5.
                     5/
                        7
                 5-Minute Check
1. Name the multiplicative inverse of 12/5.

Estimate the solution to each equation. Then solve. Write
    the solution in simplest form.
2. x = -6  1½
                 5-Minute Check
1. Name the multiplicative inverse of 12/5.

Estimate the solution to each equation. Then solve. Write
    the solution in simplest form.
2. x = -6  1½                 -4
                     5-Minute Check
1. Name the multiplicative inverse of 12/5.

Estimate the solution to each equation. Then solve. Write
    the solution in simplest form.
2. x = -6  1½

3. n = 5/12  7/15
                     5-Minute Check
1. Name the multiplicative inverse of 12/5.

Estimate the solution to each equation. Then solve. Write
    the solution in simplest form.
2. x = -6  1½

3. n = 5/12  7/15            25/
                                    28
                     5-Minute Check
1. Name the multiplicative inverse of 12/5.

Estimate the solution to each equation. Then solve. Write
    the solution in simplest form.
2. x = -6  1½

3. n = 5/12  7/15

Evaluate each expression if m = 1/3 and n = -2/9
4. m/n
                     5-Minute Check
1. Name the multiplicative inverse of 12/5.

Estimate the solution to each equation. Then solve. Write
    the solution in simplest form.
2. x = -6  1½

3. n = 5/12  7/15

Evaluate each expression if m = 1/3 and n = -2/9
4. m/n                       -1½
                     5-Minute Check
1. Name the multiplicative inverse of 12/5.

Estimate the solution to each equation. Then solve. Write
    the solution in simplest form.
2. x = -6  1½

3. n = 5/12  7/15

Evaluate each expression if m = 1/3 and n = -2/9
4. m/n

5. n/m2
                     5-Minute Check
1. Name the multiplicative inverse of 12/5.

Estimate the solution to each equation. Then solve. Write
    the solution in simplest form.
2. x = -6  1½

3. n = 5/12  7/15

Evaluate each expression if m = 1/3 and n = -2/9
4. m/n

5. n/m2                       -2
6-5 Multiplying and Dividing
         Decimals
 When multiplying decimals, the number
 of decimal places in the product is the
 same as the sum of the decimal places in
 the factors.
6-5 Multiplying and Dividing
         Decimals
Example 1
Solve y = (10.7)(0.13).
        10.7              1 decimal place
6-5 Multiplying and Dividing
         Decimals
Example 1
Solve y = (10.7)(0.13).
        10.7              1 decimal place
       x0.13              2 decimal places
6-5 Multiplying and Dividing
         Decimals
Example 1
Solve y = (10.7)(0.13).
        10.7              1 decimal place
       x0.13              2 decimal places
         321
6-5 Multiplying and Dividing
         Decimals
Example 1
Solve y = (10.7)(0.13).
         10.7             1 decimal place
       x0.13              2 decimal places
          321
        1070
6-5 Multiplying and Dividing
         Decimals
Example 1
Solve y = (10.7)(0.13).
         10.7             1 decimal place
       x0.13              2 decimal places
          321
        1070
        1.391             3 decimal places
6-5 Multiplying and Dividing
         Decimals
Example 1
Solve y = (10.7)(0.13).
         10.7             1 decimal place
       x0.13              2 decimal places
          321
        1070
        1.391             3 decimal places
y = 1.391
6-5 Multiplying and Dividing
         Decimals
 To divide decimals, multiply both the
 divisor and the dividend by a power of
 ten so that the divisor is a whole
 number. Then divide.
6-5 Multiplying and Dividing
         Decimals
Example 2
Solve y = 2.25  2.5.
6-5 Multiplying and Dividing
         Decimals
Example 2
Solve y = 2.25  2.5.
Estimate: 2  2 = 1
2.5)2.25
6-5 Multiplying and Dividing
         Decimals
Example 2
Solve y = 2.25  2.5.
Estimate: 2  2 = 1
2.5)2.25            Multiply by 10 to get a whole number in
                    the divisor.
6-5 Multiplying and Dividing
         Decimals
Example 2
Solve y = 2.25  2.5.
Estimate: 2  2 = 1
2.5)2.25            Multiply by 10 to get a whole number in
                    the divisor.

    0.9
25)22.5            Divide as with whole numbers.
   225
6-5 Multiplying and Dividing
         Decimals
Example 2
Solve y = 2.25  2.5.
Estimate: 2  2 = 1
2.5)2.25            Multiply by 10 to get a whole number in
                    the divisor.

    0.9
25)22.5            Divide as with whole numbers.
   225

x = 0.9            Compare to the estimate.
 6-5 Multiplying and Dividing
          Decimals
Assignment: 18 – 48 Even, 50 – 62 All.
             Page: 298+

								
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