Question 4 - Figure it out - Page 127-132 - Chapter 5 Class 8 - Tales by Dots and Lines (Ganita Prakash II)

Transcript

Question 4 Fill in the blanks such that the mean of the collection is 6.5: 3, 11, ____, _____, 15, 6. How many possibilities exist if only counting numbers are allowed?Let the two numbers be x & y So, our data is 3, 11, x, y, 15, 6 Finding Mean Mean = (𝑆𝑢𝑚 𝑜𝑓 𝑡𝑒𝑟𝑚𝑠)/(𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑡𝑒𝑟𝑚𝑠) 6.5 = (3 + 11 + 𝑥 + 𝑦 + 15 + 6)/6 6.5 = (𝟑𝟓 + 𝒙 + 𝒚)/𝟔 6.5 × 6 = 35 + x + y 39 = 35 + x + y 39 – 35 = x + y 4 = x + y x + y = 4 Since we are asked about counting numbers Counting numbers are numbers like 1, 2, 3, 4, 5, …. Thus, we need two counting numbers whose sum is 4 Possibilities could be 1 and 3 2 and 2 Thus, 2 possibilities exist