At Burnt Mesa Pueblo, archaeological studies have used the method of tree-ring dating in an effort to determine when prehistoric people lived in the pueblo. Wood from several excavations gave a mean of (year) 1246 with a standard deviation of 42 years. The distribution of dates was more or less mound-shaped and symmetric about the mean. Use the empirical rule to estimate the following: a. a range of years centered about the mean in which about 68% of the data (tree-ring dates) will be found between and A. D.
b. a range of years centered about the mean in Which about Of the data (tree-ring dates) will be found between and A. D.
c. a range of years centered about the mean in Which almost all the data (tree-ring dates) Will be found between and A. D.

(1204 ; 1288) ;

(1162 ; 1330) ;

(1120 ; 1372)

Step-by-step explanation:

Given that:

Mean, m = 1246 years

Standard deviation, s = 42 years

68% is within one standard deviation the mean ;

Therefore 68% equals ;

mean ± 1(standard deviation)

(1246 - 1(42)) ; (1246 + 1(42))

1204 ; 1288

B) b. a range of years centered 95% about the mean in Which about Of the data (tree-ring dates) will be found between and A.D.

95% is within two standard deviation of the mean ;

Therefore 95% equals ;

mean ± 2(standard deviation)

(1246 - 2(42)) ; (1246 + 2(42)

(1246 - 84) ; (1246 + 84)

(1162 ; 1330)

c. a range of years centered about the mean in Which almost all the data (tree-ring dates) Will be found between and A.D.

About 99.7% which is within 3 standard deviations of the mean

99.7% is within 3 standard deviations of the mean ;

Therefore ;

mean ± 3(standard deviation)

(1246 - 3(42)) ; (1246 + 3(42))

(1120 ; 1372)

it's both, now can you answer my most recent question?

answer set (b) 0.5, 3/4 80% is in order from least to greatest.  

step-by-step explanation:

in order to compare rational numbers to each other, it is much easier if they are in the same form.   typically, the best form in which to evaluate rational numbers is in decimals.   in order to convert a percent to a decimal, you would divide the given percentage by 100.   you can also accomplish the conversion by moving the decimal point over two places to the left.   for example, the decimal value of 80% is 80/100, or 0.8.   in order to convert a fraction to a decimal, you need to divide the numerator by the denominator.   for example, 3/4 is 0.75.   so, for choice (b) 0.5 3/4 (0.75), 80% (0.8) is the only choice in which the numbers are in order from least to greatest.