Find phone numbers in AP whose sum is 20 and the sum of whose square i

1.	Find phone numbers in AP whose sum is 20 and the sum of whose square is 180
Answer» Let the four numbers in A.P. be.Given,Given,When\xa0a\xa0= 5 and\xa0d\xa0= 2, we getWhen\xa0a\xa0= 5 and\xa0d\xa0= –2, we getThus, four numbers in A.P. are –1, 3, 7 and 11.

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