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Multiplication by 11 73 Th e next steps are: 4 + 7 = 11 Write 1 and carry 1. Add the next digits: 0 + 4 + 1 (carried) = 5 Write ...

74 Speed Math for Kids If the answer is correct, the answers will be the same or have a diff erence of 11 or of a multiple of 11 ...

Multiplication by 11 75 MULTIPLYING BY MULTIPLES OF 11 What are factors? We read about factors in Chapter 6. We found that it is ...

76 Speed Math for Kids One last question for this chapter: how would you multiply by 55? To multiply by 55, you could multiply b ...

77 = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < ...

78 Speed Math for Kids $2.50 represents 2 dollars and 50 hundredths of a dollar. Th e fi rst digit after the decimal represents ...

Multiplying Decimals 79 We write down the problem as it is, but when we are working it out, we ignore the decimal points. +2 +4 ...

80 Speed Math for Kids tells us our decimal is in the right place. Th is is a good double-check. You should always make this che ...

Multiplying Decimals 81 that might not be apparent otherwise. We will look at some of these possibilities shortly. In the meanti ...

82 Speed Math for Kids We can also write another 0 before the decimal, because there should always be at least one digit before ...

Multiplying Decimals 83 What reference number would we use for this one? We could use 10 for the reference number for 8, but 79 ...

84 Speed Math for Kids Now, we have to place the decimal. How many digits are there after the decimal in the problem? One, the 0 ...

Multiplying Decimals 85 Now multiply 32 by 20. To multiply by 20, we multiply by 2 and by 10. 32 × 2 = 64 64 × 10 = 640 It is ea ...

86 Speed Math for Kids Test you rself Try these problems for yourself: a) 9 × 82 = b) 9 × 79 = c) 9 × 77 = d) 8 × 75 = e) 7 × 89 ...

87 = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < ...

88 Speed Math for Kids number, or three times, four times or even sixteen times the fi rst reference number. In this case I woul ...

Multiplication Using Two Reference Numbers 89 Now subtract 8 from 37. 37 – 8 = 29 Write 29 after the equals sign. (10 × 4) 8 × 3 ...

90 Speed Math for Kids Th e calculation now looks like this: (100 × 3) 96 × 289 = –4 –11 –12 Subtract 12 from 289. 289 – 12 = 27 ...

Multiplication Using Two Reference Numbers 91 the circles above. How much above? Two and 4, so we write 2 and 4 in the circles. ...

92 Speed Math for Kids Th e completed problem looks like this: +24 +2 +4 (10 × 12) 12 × 124 = 1,480 8 1,488 Answer I try to cho ...