Problem: the class mean score on a test was 40 , and the standard deviation was 15 . if jack ' s score was within 2 standard deviations of the mean , what is the lowest score he could have received ?
Rationale: "1 sd from the mean is adding and subtrating the amount if standard deviation from the mean one time . 2 sd from the mean is adding and subtracting twice . 1 sd from the mean ranges from 25 to 55 , where 55 is within sd above the mean and 25 within 1 sd below the mean 2 sd = 15 twice = 30 from the the mean , which is 55 to 25 , where 55 is within 2 sd above the mean and 30 is within 2 sd below the mean . answer = a"
annotated_formula: multiply(2, 15)