Q: The ‘Amazing Soft Drink’ company interviewed ‘k’ consumers for market research study. The study found that 2/5 of consumers preferred Zing cola to Diet Zing Cola. Of those who preferred Diet Zing, 1/6 preferred Caffeine free Diet Zing. How many consumers, in terms of ‘k’ , did not prefer Caffeine free Diet Zing?

(Target Audience: GMAT)

A. k/11

B. k/10

C. 7k/15

D. 9k/10

E. 10k/11

Answer: OPTION D

Explanation: Generic Way

Number of customers interviewed = k

Zing cola preferred by = 2/5*k

Diet zing cola preferred by = 3/5*k

Of diet zing, caffeine free diet zing = 1/6*3/5*k=3/30k

Therefore consumer did not prefer caffeine free diet zing = k-3k/30 = 27k/30 = 9k/10

OPTION D

Explanation: HolaMaven Way

Let total customer k = 30 (product of denominators 5 & 6)

Zing cola = 12

Diet zing cola = 30-12 = 18

Caffeine free diet zing  = 3

Consumers did not prefer caffeine free diet zing = 30-3 = 27

Now using k=30 in options

Option A, Eliminated

Option B, Eliminated

Option C, Eliminated

Option D, = 27

Option E, Eliminated

Thus OPTION D