Question

mr. potters physical science classes conducted an experiment to determine the density of aluminum. here are the density values each class period came up with: 1st hour = 3.1 g/ml, 2nd hour = 3.05 g/ml, 3rd hour = 1.9 g/ml, 4th hour = 2.35 g/ml, 5th hour = 4.2 g/ml, and 6th hour = 4.0 g/ml. if aluminums true density is 2.7 g/ml, how would you group the class values based on accuracy? a. group: 1st, 3rd, 5th, and 6th hours, with one recorded decimal place in their values group: 2nd and 4th hours, with two recorded decimal places in their values b. group: 3rd and 4th hours, with values under the true density group: 1st, 2nd, 5th, and 6th hours, with values over the true density c. group: 3rd hour, with a 1 value group: 4th hour, with a 2 value group: 1st and 2nd hours, with 3 values group: 5th and 6th hours, with 4 values d. group all classes as accurate

Explanation:

Step1: Compare each value with true - density

1st hour: $3.1>2.7$; 2nd hour: $3.05 > 2.7$; 3rd hour: $1.9<2.7$; 4th hour: $2.35<2.7$; 5th hour: $4.2>2.7$; 6th hour: $4.0>2.7$.

Step2: Analyze each option

Option a groups by decimal - places, not accuracy. Option c groups by number of values in a non - accuracy related way. Option d is incorrect as not all values are close to the true density. Option b groups based on whether the values are above or below the true density which is related to accuracy.

Answer:

B. Group: 3rd and 4th hours, with values under the true density
Group: 1st, 2nd, 5th, and 6th hours, with values over the true density