Answer:
27
Step-by-step explanation:
Given :
Total number of people : 36
Ratio of people who prefer red to blue
Red : Blue = 3 : 9 = 1 : 3
according to the ratio, for every 4 people, 1 prefers red and 3 prefers blue.
Expressed mathematically:
People who prefer blue = 3/4 of the total number of people
In our case, total number is 36 hence,
People who prefer blue (and hence the number of blue pens he should order),
= 3/4 x 36 = 27
