Which of the following graphs best represents the solution to the pair of equations below? y = −x + 6 y = 2x − 3 A coordinate pl
ane is shown with two lines graphed. One line passes through the y axis at 6 and through the x axis at 6. The other line passes through the y axis at negative 3 and the x axis at 1.5. The lines intersect at the point 3 comma 3. A coordinate plane is shown with two lines graphed. One line passes through the y axis at 6 and the x axis at 6. The other line passes through the y axis at 3 and the x axis at negative 1.5. The lines intersect at 1 comma 5. A coordinate plane is shown with two lines graphed. One line passes through the y axis at 6 and the x axis at negative 6. The other line passes through the y axis at negative 3 and the x axis at negative 1.5. The lines intersect at negative 3 and 3. A coordinate plane is shown with two lines graphed. One line passes through the y axis at 6 and the x axis at negative 6. The other line passes through the y axis at 3 and the x axis at 1.5. The lines intersect at negative 1 comma 5.
The answer is between $175 and $295. The standard deviation rule tells us that for distributions that have the normal shape, approximately 99.7% of the observations fall within 3 standard deviations of the mean. Indeed, 175 = 235 − 3 * 20 and 295 = 235 + 3 * 20 are exactly 3 standard deviations below and above the mean, respectively.
