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UPSC CSE CSAT 2021 · Question 35 · Arithmetic: percentage, ratio, averages, time & work

In a group of 120 persons, 80 are Indians and rest are foreigners. Further, 70 persons in the…

In a group of 120 persons, 80 are Indians and rest are foreigners. Further, 70 persons in the group can speak English. The number of Indians who can speak English is

Answer & explanation

Answer: (d) 30 or more

There are only 40 foreigners, so at most 40 of the 70 English speakers can be foreigners. At least 30 must be Indians, and the number could be higher, so the answer is '30 or more'.

  1. Foreigners = 120 − 80 = 40.
  2. Even if all 40 foreigners speak English, at least 70 − 40 = 30 English speakers are Indians.
  3. If all 70 English speakers were Indians, the number would be 70; the data do not fix it.
  4. So the number of Indians who speak English is 30 or more.

Remember · Minimum overlap of two groups = (size of A + size of B) − total; give a range when the data do not fix an exact value.

Question and answer: UPSC's official GS Paper II (2021, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·

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