Which of the following is the closest decimal approximation for √120 without exceeding 120?

1 answer

To find the closest decimal approximation for \( \sqrt{120} \), we can start by estimating the square roots of perfect squares around 120.

The perfect squares near 120 are:

  • \( 10^2 = 100 \)
  • \( 11^2 = 121 \)

From this, we know that: \[ 10 < \sqrt{120} < 11 \]

Next, we can refine our estimate. Let's try calculating \( 10.5^2 \): \[ 10.5^2 = 110.25 \] Since \( 110.25 < 120 \), we know that \( \sqrt{120} > 10.5 \).

Now let's try \( 10.9^2 \): \[ 10.9^2 = 118.81 \] Since \( 118.81 < 120 \), we can conclude that \( \sqrt{120} > 10.9 \).

Next, let's try \( 10.95^2 \): \[ 10.95^2 = 120.6025 \] Since \( 120.6025 > 120 \), we know that \( \sqrt{120} < 10.95 \).

Now let's try \( 10.92^2 \): \[ 10.92^2 = 119.2064 \] Since \( 119.2064 < 120 \), we know that \( \sqrt{120} > 10.92 \).

Next, let's check \( 10.93^2 \): \[ 10.93^2 = 119.4649 \] Since \( 119.4649 < 120 \), we also know \( \sqrt{120} > 10.93 \).

Finally, let’s check \( 10.94^2 \): \[ 10.94^2 = 119.6356 \] Since \( 119.6356 < 120 \), we conclude that \( \sqrt{120} > 10.94 \).

Summarizing our findings:

  • We have \( 10.9 < \sqrt{120} < 10.95 \) and \( 10.93 < \sqrt{120} < 10.94 \).
  • Given \( 10.94^2 < 120 \) and \( 10.95^2 > 120 \), we can conclude that the closest decimal approximation for \( \sqrt{120} \) without exceeding 120 is approximately \( 10.94 \).

So, the closest decimal approximation for \( \sqrt{120} \) without exceeding 120 is approximately: \[ \boxed{10.94} \]