Question 4 - Figure it out - Page 101 - Chapter 5 Class 7 - Connecting the Dots... (Ganita Prakash II)

Transcript

Question 4 Two friends are training to run a 100 m race. Their running times over the past week are given in seconds — Nikhil: 17, 18, 17, 16, 19, 17, 18; Sunil: 20, 18, 18, 17, 16, 16, 17. Who on average ran quicker?We need to find who ran quicker, i.e. we need to find who took lesser time to run the race We find Average time per race for both friends Nikhil Nikhil takes 17, 18, 17, 16, 19, 17, 18 seconds Number of attempts = 7 Now, Average time taken per attempt = (𝑇𝑜𝑡𝑎𝑙 𝑇𝑖𝑚𝑒 𝑡𝑎𝑘𝑒𝑛 𝑖𝑛 𝑎𝑙𝑙 𝑎𝑡𝑡𝑒𝑚𝑝𝑡𝑠)/(𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑎𝑡𝑡𝑒𝑚𝑝𝑡𝑠) = (17 + 18 + 17 + 16 + 19 + 17 + 18)/7 = 𝟏𝟐𝟐/𝟕 = 17.428… Sunil Sunil takes 20, 18, 18, 17, 16, 16, 17 seconds Number of attempts = 7 Now, Average time taken per attempt = (𝑇𝑜𝑡𝑎𝑙 𝑇𝑖𝑚𝑒 𝑡𝑎𝑘𝑒𝑛 𝑖𝑛 𝑎𝑙𝑙 𝑎𝑡𝑡𝑒𝑚𝑝𝑡𝑠)/(𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑎𝑡𝑡𝑒𝑚𝑝𝑡𝑠) = (20 + 18 + 18 + 17 + 16 + 16 + 17)/7 = 𝟏𝟐𝟐/𝟕 = 17.428… Thus, for both of them Average time taken per attempt is same 𝟏𝟐𝟐/𝟕 Since average is same, we can say Neither ran quicker. Both had the exact same average time (17.43 seconds). Sunil Sunil takes 20, 18, 18, 17, 16, 16, 17 seconds Number of attempts = 7 Now, Average time taken per attempt = (𝑇𝑜𝑡𝑎𝑙 𝑇𝑖𝑚𝑒 𝑡𝑎𝑘𝑒𝑛 𝑖𝑛 𝑎𝑙𝑙 𝑎𝑡𝑡𝑒𝑚𝑝𝑡𝑠)/(𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑎𝑡𝑡𝑒𝑚𝑝𝑡𝑠)= (20 + 18 + 18 + 17 + 16 + 16 + 17)/7 = 𝟏𝟐𝟐/𝟕 = 17.428… Thus, for both of them Average time taken per attempt is same 𝟏𝟐𝟐/𝟕 Since average is same, we can say Neither ran quicker. Both had the exact same average time (17.43 seconds).