Sophia Statistics Unit 1 Milestone 1

the sum of squares for a sample containing 51 items equals 200, what is the standard deviation? •  2.00 • 3.92 • 4.00 • 1.98 RATIONALE The standard deviation is found by dividing the sum of squares by (n-1) and taking the square root so here it would be: CONCEPT Calculating Standard Deviation and Variance 2 Michael checked several car dealerships around town for the make and model he wanted to purchase. He received eight different quotes: $27,345 $26,780 $27,345 $29,785 $26,450 $29,480 $26,700 $26,995 What is the average car price? • $27,607 • $28,415 •  $27,610 • $27,345 RATIONALE The average, or mean, is found by adding all the values and dividing by the number of data points, in this case, eight different quotes. ($27,345 + $26,780 + $27,345 + $29,785 + $26,450 + $29,480 + $26,700 + $26,995) / 8 = $220,880 / 8 = $27,610. CONCEPT Calculating the Center of Data 3 Two drains in Bill's house were clogged. After considering the selection of drain cleaners at the hardware store, Bill chose a brand that claimed to be effective with just one use. Back at home, Bill eventually had to use the cleaner three times before the drains cleared, but he was still satisfied with the product. Which of the following correctly describes the sample? • The number of drains the product's manufacturer tested • The products Bill chose • All of the different types of drain cleaning products •  The number of times it takes for Bill's drains to unclog