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Misc 2 - If sum of three numbers in AP is 24, product is 440 - Miscellaneous

Misc 2 - Chapter 9 Class 11 Sequences and Series - Part 2
Misc 2 - Chapter 9 Class 11 Sequences and Series - Part 3
Misc 2 - Chapter 9 Class 11 Sequences and Series - Part 4

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Misc 2 If the sum of three numbers in A.P., is 24 and their product is 440, find the numbers. Let the three numbers in A.P. be a d, a, a + d. Sum of the three numbers is 24 (a d) + (a) + (a + d) = 24 a + a + a + d d = 24 3a + 0 = 24 3a = 24 a = 24/3 a = 8 Also, it is given that product of three number is 440 i.e. (a d) (a) (a + d) = 440 (a d)(a + d)a = 440 (a2 d2)a = 440 Putting a = 8 (82 d2)8 = 440 82 d2 = 440/8 64 d2 = 55 64 55 = d2 9 = d2 d2 = 9 d = 9 d = 3 So, d = 3 , d = 3 When d = 3 & a = 8 The numbers are a d = 8 3 = 5 a = 8 a + d = 8 + 3 = 11 Hence the numbers are 5, 8, 11 When d = -3 & a = 8 The number are a d = 8 (-3) = 8 + 3 = 11 a = 8 a + d = 8 + (-3) = 8 3 = 5 Hence the numbers are 11, 8, & 5 Hence the numbers are 5, 8, 11 for a = 8, d = 3 and 11, 8, & 5 for a = 8, d = -3

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Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.