Question $12(3\mathrm{.}5$ points$)$

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Demand $($Units$)$

Frequency $($Weeks$)$

Prob

Cumulative Probability

Demand

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$0$

$110$

$110$

$16$

$0\mathrm{.}16$

$0\mathrm{.}16$

$120$

$120$

$23$

$0\mathrm{.}23$

$0\mathrm{.}39$

$130$

$130$

$31$

$0\mathrm{.}31$

$0\mathrm{.}70$

$140$

$140$

$30$

$0\mathrm{.}30$

$1\mathrm{.}00$

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Total

$100$

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What is the probability of demand being either $120$ or $140$ units?

Question $12$ options:

$\mathrm{.}7$

$\mathrm{.}53$

$1\mathrm{.}0$

$\mathrm{.}84$