Question

Find the cost of digging a cuboidal pit of dimensions 8 cm x 7.5 m x 7 m at the
rate of 25 per mº³.​

Answer 1

Answer:

$\huge\bf\underline{\underline{solution}}$

l = 8m

b= 7.5m

h = 7m

volume of cuboid = (l×b×h) m³

= (8×7.5×7)m³

= 420m³

cost of digging 1m³ = ₹25

cost of digging 420m³ = ₹25× 420

= ₹10500

∴ the cost of digging pit is ₹10,500

Answer 2

★GIVEN★

• A cuboidal pit of dimensions 8 cm x 7.5 m x 7 m.
• Cost of digging the pit at a rate of 25 per m³.

★To Find★

The cost.

★SOLUTION★

• 8 cm in m = 8 × 1/100 = 0.08 m.

We know that volume of a cuboid is,

$\large{\green{\underline{\boxed{\bf{Volume=Length\times\:Breadth\times\:Height}}}}}$

where,

• Length = 0.08 m
• Breadth = 7.5 m
• Height = 7 m.

According to the question,

$\large\implies{\sf{Volume=Length\times\:Breadth\times\:Height}}$

$\large\implies{\sf{Volume=0.08\times7.5\times7}}$

$\large\therefore\boxed{\bf{Volume=4.2\:m^3.}}$

Cost,

$\large{\green{\underline{\boxed{\bf{Total\:Cost=Cost\:m^3\times\:Volume}}}}}$

Putting the values,

$\large\implies{\sf{Total\:Cost=25\times4.2}}$

$\large\therefore\boxed{\bf{Total\:Cost=Rs.105}}$

So, cost of digging the cuboidal pit is Rs. 105.