Question

A family of 8 people have enough stock of rice to last for 30 days. Due
to the arrival of some relatives, this food was consumed in 20 days.
How many guests joined the family?

Answer 1

Answer:

Number of people              8       x

Stock of rice for days       30     20

This a case of inverse proportion because when number of person increases the stock of rice will last for less days.

⇒ 8*30 = x*20

x = 240/20

x = 12 guests

Now, 8 people were already in the family. Then 12 - 8 = 4 guests joined the family.

Answer 2

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

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

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• Family of 8 people have enough stock of rice to last for 30 days

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• Due to the arrival of some relatives, this food was consumed in 20 days.

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

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• How many guests joined the family

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

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Let the modified family contains 'x' members

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We got that 8 member can finish the rice in 30 days.

So 'x' member will finish rice in 20 days.

$\:\:$

Number of people              8       x

Stock of rice for days       30     20

$\:\:$

This a case of inverse proportion

because when number of person increases the stock of rice will last for less days.

$\:\:$

$\sf \longmapsto 8\times30 = x\times20$

$\:\:$

$\sf \longmapsto 240 = 20x$

$\:\:$

$\sf \longmapsto x = \dfrac { 240 } { 20 }$

$\:\:$

$\bf \dashrightarrow x = 12$

$\:\:$

Hence by the new condition the family contains 12 members , now, 8 people were already in the family.

$\:\:$

$\underline{\bold{\texttt{New guests :}}}$

$\:\:$

Then 12 - 8 = 4 guests joined the family.

$\rule{200}5$