Evaluate the
`42.21 div 2.1 `

Answer

To evaluate \( 42.21 \div 2.1 \), we can follow these steps:

### Step 1: Set up the division
We write the division as \( 42.21 \div 2.1 \). Here, \( 42.21 \) is the dividend (the number being divided), and \( 2.1 \) is the divisor (the number we are dividing by).

### Step 2: Eliminate the decimal
To make the division easier, we can eliminate the decimal point. We do this by multiplying both the divisor and the dividend by 10 (since \( 2.1 \) has one decimal place).

- New divisor: \( 2.1 \times 10 = 21 \)
- New dividend: \( 42.21 \times 10 = 422.1 \)

So now we need to evaluate \( 422.1 \div 21 \).

### Step 3: Perform the division
Now we will divide \( 422.1 \) by \( 21 \).

1. **Divide the whole number part**:
- \( 21 \) goes into \( 42 \) (the first two digits of \( 422 \)) exactly \( 2 \) times because \( 21 \times 2 = 42 \).
- Subtract \( 42 \) from \( 42 \) to get \( 0 \).
- Bring down the next digit, which is \( 2 \), making it \( 02 \).

2. **Continue the division**:
- \( 21 \) does not go into \( 2 \) (the next digit), so we place a \( 0 \) in the quotient.
- Bring down the next digit, which is \( 1 \), making it \( 21 \).

3. **Final division**:
- \( 21 \) goes into \( 21 \) exactly \( 1 \) time because \( 21 \times 1 = 21 \).
- Subtract \( 21 \) from \( 21 \) to get \( 0 \).

### Step 4: Place the decimal point
Since we initially moved the decimal point one place to the right, we need to place the decimal point in our answer. The result of the division is \( 20.1 \).

### Final Answer
Thus, \( 42.21 \div 2.1 = 20.1 \).

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