Conditions:

- The multiplicand is a two digits number.
- The multiplier is 33.

Note:

Before this, we have learned a trick on how to multiply a two digits number by 99. Therefore, when multiplying a number by 33, we may convert 33 to 99/3. Since multiplying a number by 99 can be done easily, hence this calculation can be completed easily.

**Example 1**:

78 x 33 = ?

**Answer**:

$$\begin{array}{l}78\times 33\\ =78\times \frac{99}{3}\\ =26\times 99=2574\end{array}$$

Note: 78 is a multiple of 3. Therefore, you are advised to divide 78 by 3 before moving on to the multiplication.

**Example 2**:

267 x 33 = ?

**Answer**:

$$\begin{array}{l}267\times 33\\ =267\times \frac{99}{3}\\ =89\times 99=8811\end{array}$$

Even though 267 is not a two digits number, it can still be solved by using this trick because it is a multiple of 3, and after divided by 3, it is reduced to 87, which is a two digit number.

**Example 3**:

47 x 33 = ?

**Answer**:

$$\begin{array}{l}47\times 33\\ =47\times \frac{99}{3}\\ =\frac{4653}{3}=1551\end{array}$$

47 is not a multiple of 3. Therefore you are advised to do the multiplication first, then only divide the product by 3.

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