At a chocolate store, 70% of the items are dark chocolate and 30% are milk chocolate. Also 20% of the items have nuts and 80% are nut free. If 90% of the dark chocolate items are nut free, what percent of all the items are milk chocolate with nuts?

A. 13%

B. 17%

C. 20%

D. 35%

E. None of the above

A. 13%

Step-by-step explanation:

let's suppose there's 1000 bars of chocolate in general

70 % dark = 700 dark choco bars

30 % milk = 300 milk choco bars

20 % have nuts = 200 bars have nuts

80 % don't have nuts = 800 bars don't have nuts

if 90 % of dark chocolate bars don't have nuts, that means 630 dark chocolate bars don't have nuts, but 70 have nuts

200 bars in general have nuts, if only 70 dark chocolate bars have nuts,

200 - 70 = 130

130 = 13%