Question

students of a class are made to stand in rows if 1 students is extra there would be two rows less.if one is less in a row there would be three rows more find the number of students in the class​

Answer 1

$\blue{\bold{\underline{\underline{Answer:}}}}$

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$\green{\underline \bold{Given :}}$

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• If 1 students are extra in a row, there would be 2 row less

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• If 1 students are less in a row there would be 3 rows more

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$\red{\underline \bold{To \: Find:}}$

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• Number of students in the class.

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$\large{\orange{\underline{\tt{Solution :-}}}}$

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Let the number of rows be 'x' rows

Number of students in each row be 'y' students

Then the total number of students in a class = xy students.

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$\purple{\underline \bold{According \: to \: the \ question :}}$

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⇒ (x − 2)(y + 1) = xy

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⇒ xy + x − 2y − 2 = xy

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⇒ x − 2y = 2 ---------(i)

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And

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⇒ (x + 3)(y − 1) = xy

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⇒ xy − x + 3y − 3 = xy

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⇒ −x + 3y = 3 ------(ii)

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⇒ x − 2y = 2

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⇒ −x + 3y = 3

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On adding , y = 5 students.

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$\underline{\bold{\texttt{Putting y = 5 in equation (i)}}}$

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⇒ x − 2(5) = 2

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⇒ x = 12 rows.

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∴ Total number of students in a classroom

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⇒ (12 × 5)students = 60 students.

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