A piece of metal was weighed on a laboratory balance four times and gave the following results: 15.75, 15.72, 15.79, and 15.76 g. Determine the average mass and the standard deviation.
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- In order to find the density of a solution of unknown density, 10 mL of solution was drawn into a clean and dry beaker three times with a pipette and weighed and the weighing results were found to be 65.1452 g, 64.9982 g, 65.1027 g. Calculate the density of the solution and the standard deviation of the measurements, since the empty weight of the beaker is 52.2461 g.Which statement is true? Question 12 options: Precision is measured by standard deviation. Precision is measured by error or relative error. Accuracy is measured by the standard deviation.Determine the Average Mass and the Standard Deviation for the following data: Mass of pennies in grams = 1.5021, 1.4736, 1.4966, 1.5164, 1.5420, 1.4699 g. Average Mass grams +/- Standard Deviation grams
- You have measured the mass of samples A,B,C,D, and E on the analytical balances in our chemistry lab. Determine the standard deviation of these measurements and report your answer with at least 3 significant figures. mass A 103.039 g B 104.404 g C 103.32 g D 104.285 g E 104.123 gThere are three types of error in the laboratory: random error, systematic error, and gross error. Elaborate how can you use standard deviation and percent error in identifying the errors made in the measurement.In a certain population, body weights are normally distributed with a mean of 152 pounds and a standard deviation of 26 pounds. How many people must be surveyed if we want to estimate the percentage who weigh more than 180 pounds? Assume that we want 96% confidence that the error is no more than 4 percentage points.
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- There samples of the same metal are weighed and their masses are found to be 42.02 g.4.63 g, and 44.16g. The corresponding volumes are 455 ml., 5.11 ml., and 4.84 m., respectively. Determine the density, d, of the metal and calculate the standard deviation of the density. d= The densities of several metals are given in the table. Metal (g/cm) aluminum 2.70 iron 7.87 cobalt 8.90 copper 8.96 gold 19.3 glemt Which of the metals could the sample be? gold cobalt D aluminoun copper g/cm³The Calcium content of a banana sample was homogenized and measured. Are the results comparable? Do they have the same precision? Please use data given.over a course of multiple trials a student measures the density of methanol to be 0.707 g/mL, 0.799 g/mL, and 0.780 g/mL. calculate the average density, the deviation of each measurement and standard deviation of all data points.