Question

A factory manufactures 1,20,000 pencils daily. The pencils are cylindrical in shape, each
of length 15 cm and circumference 1.5 cm. Find the cost of colouring the curved surfaces
of the pencils manufactured in one day at 0.05 per
dm​

Answer 1

no: of pencil manufactured in one day=120000 1 decimeter (dm)=10(cm) length=25cm=(25/10) dm=2.5dm circumference=1.5dm curved surface area= circumference×lenth=2.5×0.15

Answer 2

Answer:

$\sf Cost \: of \: colouring \: the \: curved \: surfaces \: of \: the \: pencils \: manufactured \: in \: one \: day = Rs 1650$

Step-by-step explanation:

$\huge \text{Given}$

A Factory manufactures 1,20,000 daily .

Dimensions of the Pencil

Length(l) = 15 cm

Circumference = 1.5 cm

Circumference = 2πr

$\huge \text{Solution}$

We know that ,

(Curved Surface Area) CSA of cylinder = circumference×height = (2πr )h

$\bigstar$ CSA of one pencil = 1.5× 15

                               =   22.5 cm²

We know that ,

1 dm² = 100 cm²

$\bigstar$ So the CSA of one pencil = 22.5 = 0.225  dm².

∵ The factory manufactures 1,20,000 pencils

$\bigstar$ Total CSA of Pencil produced in a day = CSA of  1,20,000 pencils

$\bigstar$ Total CSA of 1,20,000 pencils = 1,20,000 × 0.225

                                                   = 27000 dm²

$\bigstar$ Cost of colouring  the curved surfaces of the pencils manufactured in one day at ₹ 0.05 per dm​² = 27000 × 0.05 = ₹ 1350