Beside rounding off the numbers, can you suggest another method to estimate the following expression?

Question

(12.37+13.93+11.87+12.64+13.45)/5

Answer 1

Certainly! Besides rounding off the numbers, another method to estimate the average of the expression \((12.37 + 13.93 + 11.87 + 12.64 + 13.45)/5\) is to use the method of truncation. This involves simplifying the numbers by dropping the decimal portion to focus on the whole number part, making it easier to add them up quickly.

Here's how you can do it:

1. Truncate each number to its whole number:

   • 12.37 becomes 12
   • 13.93 becomes 13
   • 11.87 becomes 11
   • 12.64 becomes 12
   • 13.45 becomes 13

2. Now, sum these truncated values: \[ 12 + 13 + 11 + 12 + 13 = 61 \]

3. Divide the sum by the number of values (5): \[ \frac{61}{5} = 12.2 \]

So, using truncation, you estimate that the average is approximately \( 12.2 \). This method provides a reasonably quick estimate while being an alternative to rounding.