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Find the whole numbers which when decreased by 20 is equal to 69 times the reciprocal of the members.
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Let the whole number be x as it is decreased by 20
⇒ (x - 20) = 69. (1/2)
⇒ ЁЭСе. 20 = 69. (1/ЁЭСе)
⇒ ЁЭСе(ЁЭСе - 20) = 69
⇒ ЁЭСе2 - 20ЁЭСе - 69 = 0
⇒ ЁЭСе2 - 23 + 3ЁЭСе - 69 = 0
⇒ ЁЭСе(ЁЭСе - 23) + 3(ЁЭСе - 623) = 0
⇒ (x - 23) (x + 3) = 0
⇒ x = 23; x = -3
As the whole numbers are always positive, x = -3 is not considered.
∴ The whole number x = 23.
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