Question

If the cost of painting 1 m2 of wooden board is Rs. 5, then the cost of painting a

wooden rectangular prism of sides 4 m, 3 m, and 5 m is:​

Answer 1

Answer :

• Rs . 470 is the cost of painting a wooden painting rectangular prism of sides 4m , 3m and 5m

Given :

• If the cost of painting 1m² of wooden board is Rs.5

To find :

• Cost of painting a wooden rectangular prism of sides is 4m , 3m and 5m

Solution :

Given that,

• Length = 4m
• Breadth = 3m
• Height = 5m

As we know that,

• Surface area of rectangular prism = 2(lb + bh + lh)

》 2((4)(3) + (3)(5) + (4)(5)

》2(12 + 15 + 20)

》2(47)

》94 m²

Hence,

• Cost of painting 1m² = Rs .5 (Given)
• Cost of painting 94m² = 94 × 5 = 470 Rs

Hence, Rs . 470 is the cost of painting a wooden painting rectangular prism of sides 4m , 3m and 5m

Answer 2

Correct Question :-

• If the cost of painting 1 m² of wooden board is Rs. 5, then the cost of painting a wooden rectangular prism of sides 4 m, 3 m, and 5 m is:

Given :-

• If the cost of painting 1 m² of wooden board is Rs. 5

To find :-

• Find the cost of painting a wooden rectangular prism of sides is 4 m, 3 m, and 5 m ?

★ $\large\underline{\frak{As \: we \: know \: that,}}$

$\large\dag$ Formula Used :

• $\boxed{\bf{Surface\:area\:of\:rectangle\:=\:2(\: Length\: ×\:Breadth\:+\: Breadth\: ×\:Height\:+\: Length\:×\: Height)}}$

Solution :-

• Length = 4 m
• Breadth = 3 m
• Height = 5 m

• Putting the values,

:$\implies$2( 4 )( 3 ) + ( 3 )( 5 ) + ( 4 )( 5 )

$~~~~~$:$\implies$2( 12 + 15 + 20 )

$~~~~~~~~~~$:$\implies$2( 47 )

$~~~~~~~~~~~~~~~$:$\implies$${\underline{\boxed{\pink{\frak{94~m²}}}}}$★

$\therefore$ Hence,

• Cost of painting 1 m² = $\large\underline{\rm{Rs.~5}}$

• Cost of painting 94 m² = 94 × 5 = $\large\underline{\rm{Rs.~470}}$

$\large\dag$ Hence Verified !!

• $\large\underline{\rm{Rs.~470}}$is the cost wooden painting cost of rectangular prism of sides 4 m, 3 m, and 5 m.