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The product of three numbers in A.P. is 224, and the largest number is 7 times the smallest. Find the numbers - Mathematics

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प्रश्न

The product of three numbers in A.P. is 224, and the largest number is 7 times the smallest. Find the numbers

योग

उत्तर

Let the three numbers in A.P. be a – d, a, a + d (d > 0)

Now (a – d) a (a + d) = 224

⇒ a (a2 – d2) = 224  .....(1)

Now, since the largest number is 7 times the smallest

i.e., a + d = 7(a – d)

Therefore, d = `(3"a")/4`

Substituting this value of d in (1), we get

`a(a^2 - (9a^2)/16)` = 224

a = 8

And d = `(3a)/4 = 3/4 xx 8` = 6

Hence, the three numbers are 2, 8, 14.

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अध्याय 9: Sequences and Series - Solved Examples [पृष्ठ १५२]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 11
अध्याय 9 Sequences and Series
Solved Examples | Q 6 | पृष्ठ १५२

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