Question 7 - Figure it out - Page 86, 87 - Chapter 4 Class 7 - Another Peek beyond the Point (Ganita Prakash II)

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Question 7 If the perimeter of a regular polygon with 12 sides is 208.8 cm, what is the length of its side?We know that Perimeter of regular polygon = Length of each side × Number of sides (𝑃𝑒𝑟𝑖𝑚𝑒𝑡𝑒𝑟 𝑜𝑓 𝑅𝑒𝑔𝑢𝑙𝑎𝑟 𝑃𝑜𝑙𝑦𝑔𝑜𝑛)/(𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑠𝑖𝑑𝑒𝑠)= Length of each side Length of each side = (𝑷𝒆𝒓𝒊𝒎𝒆𝒕𝒆𝒓 𝒐𝒇 𝑹𝒆𝒈𝒖𝒍𝒂𝒓 𝑷𝒐𝒍𝒚𝒈𝒐𝒏)/(𝑵𝒖𝒎𝒃𝒆𝒓 𝒐𝒇 𝒔𝒊𝒅𝒆𝒔) Putting values Length of each side = (𝑃𝑒𝑟𝑖𝑚𝑒𝑡𝑒𝑟 𝑜𝑓 𝑅𝑒𝑔𝑢𝑙𝑎𝑟 𝑃𝑜𝑙𝑦𝑔𝑜𝑛)/(𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑠𝑖𝑑𝑒𝑠) = (𝟐𝟎𝟖.𝟖)/𝟏𝟐 = 208.8 × 1/12 Removing decimals = 𝟐𝟎𝟖𝟖/𝟏𝟎 ×𝟏/𝟏𝟐 = 2088/12 ×1/10 Dividing fraction by 4 = 522/3 ×1/10 Dividing fraction by 3 = 174 × 𝟏/𝟏𝟎 = 174/10 = 17.4 cm Thus, each side is 17.4 cm