Multiplication Strategy: Doubling and Halving
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We can simplify some multiplication problems using doubling and halving. 1. Use the strategy of doubling one factor and halving the other to help simplify and solve the following problems:
Example: 5 x 16 = 10 x 8 = 80 or 5 x 16 = 10 x 8 = 20 x 4 = 80
a) 5 x 68 = ?
b) 3 x 16 = ?
c) 16 x 30 = ?
d) 18 x 40 = ?
e) 35 x 20 = ?
f) 25 x 16 = ?
g) 50 x 24 = ?
h) 500 x 28 = ?
2. Does this strategy always work? Explain when the strategy of doubling and halving is useful to simplify a multiplication problem.
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We can simplify some multiplication problems using doubling and halving. 1. Use the strategy of doubling one factor and halving the other to help simplify and solve the following problems:
Example: 5 x 16 = 10 x 8 = 80 or 5 x 16 = 10 x 8 = 20 x 4 = 80
a) 5 x 68 = ?
b) 3 x 16 = ?
c) 16 x 30 = ?
d) 18 x 40 = ?
e) 35 x 20 = ?
f) 25 x 16 = ?
g) 50 x 24 = ?
h) 500 x 28 = ?
2. Does this strategy always work? Explain when the strategy of doubling and halving is useful to simplify a multiplication problem.