तीन भाषा समूहों (हिंदी, अंग्रेजी और रूसी) का प्रतिनिधित्व करने वाले एक वेन आरेख में, यदि संबंधित ओवरलैपिंग क्षेत्रों में लोगों की संख्या 4, 3, 5 और 2 है (जहां 2 तीनों समूहों से संबंधित हैं), तो कम से कम दो भाषा समूहों से संबंधित लोगों की संख्या कितनी है?

Among 100 people, 40 people like tea, 58 people like coffee, and 26 people like both tea and coffee. Find the number of persons who like neither tea nor coffee.

In an examination of 500 candidates comprising tests in English, Hindi, and Mathematics, the failure counts in individual and combined subjects are given as follows: - Failed in English and Hindi only = 9 - Failed in English and Mathematics only = 12 - Failed in Hindi and Mathematics only = 13 - Failed in all three subjects = 5 What is the percentage of candidates who failed in at least two subjects?