Another Peek Beyond the Point | IT

Question 8

Suppose we know that 596 × 248 = 147808, can you immediately write down the product of 5.96 × 24.8?

Solution

We use the whole number product to find the decimal product.

Step 1 — Look at the whole numbers

We are given a multiplication. It involves whole numbers. The numbers are 596 and 248. Their product is 147808.

$596 \times 248 = 147808$

$\boxed{147808}$

Step 2 — Change decimals to fractions

We need to find $5.96 \times 24.8$ . Let us write $5.96$ as a fraction. It has two decimal places. So, $5.96$ is $596$ divided by $100$ .

$5.96 = \frac{596}{100}$

Let us write $24.8$ as a fraction. It has one decimal place. So, $24.8$ is $248$ divided by $10$ .

$24.8 = \frac{248}{10}$

Step 3 — Multiply the fractions

Now we multiply these fractions. We multiply the numerators. We multiply the denominators.

$5.96 \times 24.8 = \frac{596}{100} \times \frac{248}{10}$

$= \frac{596 \times 248}{100 \times 10}$

We know $596 \times 248 = 147808$ . We know $100 \times 10 = 1000$ .

$= \frac{147808}{1000}$

To divide by $1000$ , we move the decimal point. We move it three places left. The number $147808$ has its point after $8$ .

$\boxed{147.808}$

Answer

The product of $5.96 \times 24.8$ is 147.808.

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Suppose we know that 596 × 248 = 147808, can you immediately write down the product of 5.96 × 24.8?

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