The average of 30 numbers is 1.2 . The average of the first 20 of them is 1.1 and that of the next 9 is 1 . Then the last number is: - Quantitative Aptitude MCQ Competitive Exam 2026 | ExamTest.live

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The average of 30 numbers is 1.2 . The average of the first 20 of them is 1.1 and that of the next 9 is 1 . Then the last number is:

Solution & Step-by-step Explanation

Sum of all 30 numbers = 30 \times 1.2 = 36 Sum of the first 20 numbers = 20 \times 1.1 = 22 Sum of the next 9 numbers = 9 \times 1 = 9 Sum of 29 numbers = 22 + 9 = 31 The last (30 th) number: Last number = Sum of 30 numbers - Sum of 29 numbers Last number = 36 - 31 = 5

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The average of 30 numbers is 1.2 . The average of the first 20 of them is 1.1 and that of the next 9 is 1 . Then the last number is:

5

4.6

4.9

4

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