Question

Staff employed in a UNESCO office in Paris are represented by four intersecting circles, one each for people who can read and write Russian, English, French and Spanish. The strength of people in some regions is given: \(a = 40, \quad c = 2a, \quad e = \frac{1}{2}a, \quad g = 2E\)

People who cannot read and write Russian, English and French are represented by

• A. l
• B. j
• C. h
• D. e

Hint:

If a person can't know Russian, English or French, only Spanish remains.

Answer 1

The Correct Option is D

Step 1: Translate "cannot read Russian, English and French" into a diagram condition.
A person who cannot read or write Russian, English or French, but is still counted somewhere on this diagram, must fall in the region that lies completely outside the Russian, English and French circles. Since the diagram only has four language circles in total, the only place left for such a person is inside the Spanish circle alone.

Step 2: Identify that region.
The part of the Spanish circle that does not touch any of the other three circles is the "only Spanish" pocket, labelled e.

Step 3: Eliminate the other choices.
Option A, l, and option B, j, are central regions where three circles overlap, so a person there would know at least two of Russian, English or French, which the question rules out. Option C, h, is the Russian-French overlap, so that person knows Russian, which also fails the condition.

Final Answer:
Only region e keeps a person outside Russian, English and French while still being counted on the diagram. \[ \boxed{\text{e (Option D)}} \]