One percent of the people of country X are taller than 6 ft. Two percent of the people of country Y are taller than 6 ft. There are thrice as many people in country X as in country Y. Taking both countries together, what is the percentage of people taller than 6 ft?
A. 3.0
B. 2.5
C. 1.5
D. 1.25
GATE 2014 · General Aptitude · Percentage · medium
Answer: Combined percentage of people taller than 6 ft = 1.25%. Answer: D.
Assign population values: Let N_Y = 1 unit. Then N_X = 3 units and total population = 3 + 1 = 4 units.
Count people taller than 6 ft in each country: Taller in X = 1% of 3 = 0.03 units. Taller in Y = 2% of 1 = 0.02 units. Total taller = 0.03 + 0.02 = 0.05 units.