Divide :
`142.8 div 21`

Answer

To solve the division of 142.8 by 21 step by step, follow these instructions:

### Step 1: Set Up the Division
We are dividing 142.8 (the dividend) by 21 (the divisor). We can write this as:

\[ 142.8 \div 21 \]

### Step 2: Ignore the Decimal Point Temporarily
To make the division easier, we can ignore the decimal point in 142.8 for now. We will convert it to 1428 by multiplying both the dividend and the divisor by 10 (to eliminate the decimal). So we will actually divide:

\[ 1428 \div 21 \]

### Step 3: Determine How Many Times 21 Fits into 142
Now, we look at how many times 21 fits into the first part of 1428. Since 21 is less than 142, we can calculate:

- 21 goes into 142 approximately 6 times (since \( 21 \times 6 = 126 \)).

### Step 4: Subtract and Find the Remainder
Now, we subtract 126 from 142:

\[ 142 - 126 = 16 \]

### Step 5: Bring Down the Next Digit
Next, we bring down the next digit from 1428, which is 8. This gives us:

\[ 168 \]

### Step 6: Determine How Many Times 21 Fits into 168
Now we need to see how many times 21 fits into 168.

- 21 goes into 168 exactly 8 times (since \( 21 \times 8 = 168 \)).

### Step 7: Subtract Again
Now, we subtract 168 from 168:

\[ 168 - 168 = 0 \]

### Step 8: Place the Decimal Point in the Quotient
Since we initially ignored the decimal point, we need to place it in the quotient. The quotient we have so far is 68, but since we multiplied by 10 at the beginning, we need to place the decimal point one place to the left:

So, the final answer is:

\[ 6.8 \]

### Final Answer
Thus,

\[ 142.8 \div 21 = 6.8 \]

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