A scientist estimated that a mixture would need 3 milliliters of a chemical to balance. The actual amount needed was 7 milliliters. What was the percent error of the scientist's estimation?

The percent error of the scientist's estimation is 57.14%

Step-by-step explanation:

In this question, we are to calculate percentage error of estimation.

We employ a mathematical approach as follows;

Mathematically the percent error is defied with the equation below;

The percentage error = (actual value - expected value) / expected value * 100%

From the question,

The actual value observed is 7 milliliters

The estimated value is 3 milliliters.

We now substitute these values in the equation given above to yield;

(7-3) / 7 * 100% = 4/7 * 100% = 57.14%