Question 10 - Figure it out - Page 86, 87 - Chapter 4 Class 7 - Another Peek beyond the Point (Ganita Prakash II)

Transcript

Question 10 13.5 kg of flour (aata) was distributed equally among 15 students. How much flour did each student receive? What pattern do you observe? Why are 2 and 5 related in this way? We will answer this one-by-one Now, Flour received per student = (𝑇𝑜𝑡𝑎𝑙 𝑓𝑙𝑜𝑤𝑒𝑟)/(𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑠𝑡𝑢𝑑𝑒𝑛𝑡𝑠) = (𝟏𝟑.𝟓)/𝟏𝟓 Removing decimal points = 13.5 × 1/15 = 135/10 × 1/15 = (𝟏𝟑.𝟓)/𝟏𝟓 Removing decimal points = 13.5 × 1/15 = 135/10 × 1/15 = 135/15 × 1/10 = 𝟗 × 𝟏/𝟏𝟎 = 9/10 = 09/10 = 0.9 kg Thus, each student gets 0.9 kg Second part of our question is What pattern do you observe? Why are 2 and 5 related in this way? First we calculate our values 1/(2 × 2 × 2 × 2 × 2)=0.0625/2=625/2 ×1/10000=𝟎.𝟎𝟑𝟏𝟐𝟓 1/(5 × 5 × 5 × 5 × 5)=0.0016/5=16/5 ×1/10000=𝟎.𝟎𝟎𝟎𝟑𝟐 Our pattern is The denominators are made of only 2s or only 5s. Now, When we divide 1 by 2 , we get 0.5 . When we divide 1 by 𝟓, we get 𝟎.𝟐. The pattern is that numbers made of only factors of 2 and 5 will always end (terminate) as decimals. Also, notice that 1/2=0.5 and 1/5=0.2 are "opposites" involving the number 10 ! Our pattern is The denominators are made of only 2s or only 5s. Now, When we divide 1 by 2 , we get 0.5 . When we divide 1 by 𝟓, we get 𝟎.𝟐. The pattern is that numbers made of only factors of 2 and 5 will always end (terminate) as decimals. Also, notice that 1/2=0.5 and 1/5=0.2 are "opposites"