Astudent is asked to calculate the value of 212 − 132 using the identity x2 − y2 = (x − y)(x + y). the student's steps are shown below. step 1: 212 − 132 = (a − b)(a + b) step 2: = (c)(d) step 3: = (8)(30) + 8(4) step 4: = 240 + 32 step 5: = 272 what are the values of a, b, c, and d?

the answer is b.)

< 1=< 2

d. 24+-0.114

step-by-step explanation:

the question requires us to calculate the approximate 95% confidence interval for the mean number of ounces of ketchup per bottle in the sample given the following statistics;

sample mean = 24

standard deviation, σ = 0.4

sample size , n = 49

the confidence interval for a population mean is calculated using the formula;

sample mean ± z-score*(σ/sqrt(n))

the z-score associated with a 95% confidence interval, from the standard normal tables, is;

1.96

substituting these values into the formula;

24 ± 1.96*(0.4/7)

= 24 ± 0.112

from the alternatives given, choice d is closest to the above expression;