4) Ben bought 7 notebooks for $34.50. Some of the notebooks were $3.50 each and the others were $4.25 each. If x represents the number of least expensive notebooks, which equation can be used to
find the number of least expensive notebooks purchased?
a) $7.75(7 - x) = $34.50
b) $3.50(x - 7) + 4.25x = $34.50
c) $3.50x + $4.25(8 - x) = $34.50
I
d) $3.50x + $4.25(x - 8) = $34.50
What’s the asnswer

3.17 scores on stats final. below are final exam scores of 20 introductory statistics students. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 57, 66, 69, 71, 72, 73, 74, 77, 78, 78, 79, 79, 81, 81, 82, 83, 83, 88, 89, 94 (a) the mean score is 77.7 points. with a standard deviation of 8.44 points. use this information to determine if the scores approximately follow the 68-95-99.7% rule. (b) do these data appear to follow a normal distribution? explain your reasoning using the graphs provided below.