Estimate the value of 6×2–√ . Which of the following choices is the best estimate?

9.8
7.1
8.4
6.4

1 answer

To estimate the value of \( 6 \times 2 - \sqrt{} \), we first need to clarify the expression. However, if we assume the expression meant to be \( 6 \times 2 - \sqrt{something} \), we can evaluate the multiplication first.

Calculating \( 6 \times 2 \): \[ 6 \times 2 = 12 \]

Now, we need to consider the √ (square root) part. Since no number is specified, we can't calculate √ directly, but we can make some rough assumptions.

Assuming we need to subtract the square root of a simple number (e.g. \( \sqrt{4} = 2 \) or \( \sqrt{9} = 3 \)), we can evaluate a couple of scenarios:

If we assume \( \sqrt{0} = 0 \): \[ 12 - 0 = 12 \]

If \( \sqrt{1} = 1 \): \[ 12 - 1 = 11 \]

If \( \sqrt{4} = 2 \): \[ 12 - 2 = 10 \]

If \( \sqrt{9} = 3 \): \[ 12 - 3 = 9 \]

If \( \sqrt{16} = 4 \): \[ 12 - 4 = 8 \]

If \( \sqrt{25} = 5 \): \[ 12 - 5 = 7 \]

From the possibilities above, we see:

  • \( \sqrt{16} \) gives us an estimate of \( 8 \)
  • \( \sqrt{25} \) gives us an estimate of \( 7 \)
  • Using roots of perfect squares down might yield numbers close to the selection.

Thus, the best estimate is likely \( 8.4 \) given that \( 12 - 4 = 8 \) is close to this option.

Among the choices given:

  • 9.8
  • 7.1
  • 8.4
  • 6.4

The best estimate based on above calculations and rounding would be: \[ \boxed{8.4} \]