Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Typographic errors in a text are either non ord errors as when the\" is typed as

ID: 3064434 • Letter: T

Question

Typographic errors in a text are either non ord errors as when the" is typed as .teh or word errors that result in a real but incorrect word. Spell-checking software wil catch non ord errors but not word errors. Human proofreaders catch 70% of ord errors. You ask a fellow student to proofread an essay in which you have deliberately made 15 word errors (a) lfthe student matches the usual 70% rate, what is the distribution of the number of errors caught? what is numb (b) Missing 7 or more out of 15 errors seems a poor performance. What is the probability that a proofreader who catches 70% of word errors misses 7 or more out or 157(Round your answer to four decimal places.) misses 7

Explanation / Answer

Solution :
Given that n = 15,p = 0.7

a) => caught,the number caught is B(15,0.7)
=> missed,the number missed is B(15,0.3)

b) P(7 <= x <= 15) =

= P(x = 7) + P(x = 8) + P(x = 9) + P(x = 10) + P(x = 11) + P(x = 12) + P(x = 13) + P(x = 14) + P(x = 15)

= 0.0348 + 0.0811 + 0.1472 + 0.2061 + 0.2186 + 0.1700 + 0.0916 + 0.0305 + 0.0047
= 0.9846