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title: Untitled

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## 速算題 （一）

<span>1. $35 \times 16 =$<!-- .element: class="fragment" data-fragment-index="1" --></span>
<span>2. $28 \times 25 =$<!-- .element: class="fragment" data-fragment-index="2" --></span>
<span>3. $375 \times 16 =$<!-- .element: class="fragment" data-fragment-index="3" --></span>
<span>4. $24 \times 75 =$<!-- .element: class="fragment" data-fragment-index="4" --></span>
<span>5. $52 \times 175 =$<!-- .element: class="fragment" data-fragment-index="5" --></span>

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## 速算題 （一）︰答案
<span>1. $35 \times 16 =$<!-- .element: class="fragment" data-fragment-index="1" --></span> <span> $560$<!-- .element: class="fragment" data-fragment-index="2" --></span>

<span>2. $28 \times 25 =$<!-- .element: class="fragment" data-fragment-index="3" --></span> <span>$700$<!-- .element: class="fragment" data-fragment-index="4" --></span>

<span>3. $375 \times 16 =$<!-- .element: class="fragment" data-fragment-index="5" --></span> <span>$6000$<!-- .element: class="fragment" data-fragment-index="6" --></span>

<span>4. $24 \times 75 =$<!-- .element: class="fragment" data-fragment-index="7" --></span> <span>$1800$<!-- .element: class="fragment" data-fragment-index="8" --></span>

<span>5. $52 \times 175 =$<!-- .element: class="fragment" data-fragment-index="9" --></span> <span>$9100$<!-- .element: class="fragment" data-fragment-index="10" --></span>




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## 速算題 （一）︰解答
1.  $35 \times 16$
  = $5 \times 7 \times 4 \times 4$
  = $7 \times 4 \times 5 \times 4$
  = $28 \times 20$
  = $560$

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### 速算題 （一）︰解答
2.  $28 \times 25$
  = $7 \times 4 \times 25$
  = $7 \times 100$
  = $700$
  
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## 速算題 （一）︰解答
3.  $375 \times 16$
  = $125 \times 3 \times 25$
  = $7 \times 100$
  = $700$

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## 速算題 （一）︰解答
4.  $24 \times 75$
  = $6 \times 4 \times 25 \times 3$
  = $6 \times 3 \times 25 \times 4$
  = $1800$
  
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## 速算題 （一）︰解答
5.  $52 \times 175$
  = $13 \times 4 \times 25 \times 7$
  = $13 \times 7 \times 25 \times 4$
  = $9100$