A student estimated the sum 7.95 8.11 78.5 8.05 79.4 0.815 as: all the numbers begin with a 7 or 8, so use cluster estimation. 8 8 80 8 80 0.8 = 184.8 explain why this reasoning is not accurate.

Estimation is a sort of rounding off. Estimation is employed in daily life as well as in areas such as mathematics and physics. Many physical values, such as money, distance traveled, length measured, and so on, are approximated via rounding off the exact figure to the next whole number.

The following are the decimal rounding-off rules:

Look at the righthand side of the rounded digit.
Consider the digits just on right-hand side to be equivalent to zero if they are less than 5.
If the numbers on the right are larger than or equal to 5, add +1 to the that digit and ignore all other digits.

Now, according to the question;

The given added vales are-

7.95 + 8.11 + 78.5 + 8.05 + 79.4 + 0.815

Round-off the values in the following manner

= 8 + 8 + 79 + 8 + 79 + 0.9

= 182.9

As a result, the clustered point of three numbers is incorrect.

To know more about the rounding-off, here

https://brainly.com/question/10679598

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The correct question is-

A student estimated the sum

7.95 + 8.11 + 78.5 + 8.05 + 79.4 + 0.815 as:

All the numbers begin with a 7 or 8, so use cluster estimation.

8 + 8 + 80 + 8 + 80 + 0.8 = 184.8

Explain why this reasoning is not accurate.