Question

the length of a hall is 8m more than its breadth. if the perimeter of the hall is 40m. find the cost laying a carpet at the cost of 12 per sq. m .​

Answer 1

Answer:

I = b +8

P=2 (I+b)

P=2(b+8+.b)

40=2(2b+8)

40=4b+16

40-16=4b

24=4b

b = 6m

I=b+8=6+8=14m

Area =Ixb=14x6=84m2

cost of carpet =84x12 = 1008

= Rs.1008

Answer 2

$\Large{\textbf{\underline{\underline{According\:to\:the\:Question}}}}$

Length of the hall is 8m more than its breadth

Also,

Perimeter of hall

= 40m

${\boxed{\sf\:{Cost\;of\;carpet\;Per\;Square\;metre}}}$

= ₹12

Hence,

Assume

Breadth be p m

Also,

Length = (8 + p)

Therefore,

Perimeter of Rectangle = 2(L + B)

40 = 2(8 + p + p)

40 = 2(8 + 2p)

40 = 16 + 4p

40 - 16 = 4p

24= 4p

$\tt{\rightarrow p=\dfrac{24}{4}}$

p = 6

Therefore ,

Breadth = 6m

Length = 8 + p

= 8 + 6

=14m

Now,

Area of the rectangle = L × B

= 6 × 14

= 84 m²

Hence ,

Cost

${\boxed{\sf\:{Area\;of\;carpet\times cost\;of\;laying\; carpet}}}$

= 84 × 12

=1008