Solve: Locating the Decimal Point in 2.35 × 7.6 = 1786

Question

Given the following exercise, find the correct place of the decimal point:

2.35×7.6=1786 2.35\times7.6=1786

Video Solution

Solution Steps

00:00 Solve
00:03 Convert decimal numbers to fractions
00:07 Write the number as a whole number in the numerator, and a power of 10 in the denominator
00:10 Add zeros to the denominator according to the number of digits after the decimal point
00:17 Move to the second factor, use the same method
00:30 Make sure to multiply numerator by numerator and denominator by denominator
00:39 Calculate the multiplications
00:49 Now write the numerator as a whole number
00:56 For the number of zeros in the denominator, position the decimal point
01:03 And this is the solution to the question

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Identify the decimal places in each number.
  • Step 2: Determine the total number of decimal places needed in the product.
  • Step 3: Adjust the product to include the correct number of decimal places.
  • Step 4: Select the correct answer from the choices based on this calculation.

Let's work through these steps:

Step 1: The number 2.352.35 has two decimal places, and the number 7.67.6 has one decimal place. This gives us a total of 2+1=32 + 1 = 3 decimal places needed in the product.

Step 2: Multiply the numbers as whole numbers: 235×76=17860235 \times 76 = 17860. Notice it seems like 17861786 in the problem statement, which lacks correct decimal placement.

Step 3: With a total of three decimal places needed in the result, we place the decimal point in 17861786 to make it 17.8617.86, adding those three decimal places.

Step 4: Compare this with the given options. The placement in option 2 is 17.86\text{\textbf{17.86}}, which correctly reflects the required three decimal places.

Therefore, the correct solution is \(\textbf{17.8617.86}\).

Answer

17.86 17.86