A pen stand is in shape with the base radius 3.5cm and height 10.5cm. How much cardboard will be required to make 25 such pen stand? Also find yhe value of 1 pen stand.
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Answered by
5
Hi there !!
Radius , r = 3.5 cm
Height , h = 1.5 cm
Cardboard required to make 1 pen stand = C.S.A of the cylinder + 1 Base area
C.S.A of the cylinder = πr²h
= 22/7 ×3.5 ×3.5 × 10.5
= 404 .25 cm²
Base area = πr²
= 22/7 × 3.5 × 3.5
= 38.5 cm²
Total cardboard required for 1 pen stand = 404.25 + 38.5
= 442.75 cm²
Cardboard required to make 25 pen stands = 442.75 × 25
= 11068.75 cm²
Radius , r = 3.5 cm
Height , h = 1.5 cm
Cardboard required to make 1 pen stand = C.S.A of the cylinder + 1 Base area
C.S.A of the cylinder = πr²h
= 22/7 ×3.5 ×3.5 × 10.5
= 404 .25 cm²
Base area = πr²
= 22/7 × 3.5 × 3.5
= 38.5 cm²
Total cardboard required for 1 pen stand = 404.25 + 38.5
= 442.75 cm²
Cardboard required to make 25 pen stands = 442.75 × 25
= 11068.75 cm²
Answered by
1
Answer:
Given :-
Radius - 3.5 cm
Height :- 10.5 cm
No. of pen stands - 25
Step-by-step explanation:
Surface area of one pen-stand - 2πrh + πr²
2×22/7×3.5×10.5 + 22/7×3.5×3.5
⇒385 cm² + 231 cm² = 616 cm²
Surface area of one pen-stand is 616 cm²
Surface area of 25 pen stands is 25×616 cm²
⇒ 15400 cm²
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