Saima wants to put a lace on the edge of a circular table cover of diameter 1.5 m. Find the length of the lace required and also find its cost if one meter of the lace costs ₹ 15. ( Take π = 3.14) - Mathematics

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Sum

Saima wants to put a lace on the edge of a circular table cover of diameter 1.5 m. Find the length of the lace required and also find its cost if one meter of the lace costs ₹ 15. ( Take π = 3.14)

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Solution

Circumference = 2πr

= `2pir xx 3.14 xx d/2`

= `2 xx3.14xx (1.5)/2` = 4.71 m

Cost of 1 m lace = ₹ 15

Cost of 4.71 m lace = 4.71 × 15

= ₹ 70.65

  Is there an error in this question or solution?
Chapter 11: Perimeter and Area - Exercise 11.3 [Page 223]

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NCERT Mathematics Class 7
Chapter 11 Perimeter and Area
Exercise 11.3 | Q 6 | Page 223

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