The town of Malmo, Sweden has only two late-night food options: Pizza and Kebab. All sellers of late-night food have either a street permit or a permanent store permit. 60% of all the late-night food sellers in Malmo are street vendors that serve Kebab; 20% of all the late-night food sellers who have a permanent store serve Pizza. If Malmo's ratio of total street permits to total permanent store permits is exactly 7 to 3, what percentage of all late-night food sellers in Malmo serve pizza?

A. 10%
B. 16%
C. 24%
D. 30%
E. 70%

The OA is B.

Given that, Ratio of street permits to total permanent store permits = 7 : 3
Assume total number of stores = 100

Street stores = 70
Permanent stores = 30
Street stores that serve kebab = 60 (60% of all stores)
Permanent stores that serve pizza = 6 (20% of 30 permanent stores)

. . . . . . . . . . . . . . . Street . . . . . . . . . Permanent
Pizza . . . . . . . . . . .10 . . . . . . . . . . . .6=20% of 30 . . . . . 16
Kebab . . . . . . . . . 70 . . . . . . . . . .
Total . . . . . . . . . . . 70 . . . . . . . . . . . . . . . 30 . . . . . . . . . . . 100

Put this data into statistics table (as shown above), calculate and arrive at the answer "16% of stores serve pizza"

Hence choice B is the answer.