Question 8 - Figure it out - Page 73 - Chapter 4 Class 7 - Another Peek beyond the Point (Ganita Prakash II)

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Question 8 Given that 18 × 12 = 216, find the products: (a) 18 × 1.2 (b) 18 × 0.12 (c) 1.8 × 1.2 (d) 0.18 × 0.12 (e) 0.018 × 0.012 (f) 1.8 × 12 In which of the cases above is the product less than 1?Given that 18 × 12 = 216 We use the known answer (216) and just move the decimal point based on the total decimal places in the question. (a) 𝟏𝟖 × 𝟏.𝟐→1 decimal place →𝟐𝟏.𝟔 (b) 𝟏𝟖 × 𝟎.𝟏𝟐→2 decimal places →𝟐.𝟏𝟔 (c) 𝟏.𝟖 × 𝟏.𝟐→1+1=2 decimal places →𝟐.𝟏𝟔 (d) 𝟎.𝟏𝟖 × 𝟎.𝟏𝟐→2+2=4 decimal places →𝟎.𝟎𝟐𝟏𝟔 (e) 𝟎.𝟎𝟏𝟖 × 𝟎.𝟎𝟏𝟐→3+3=6 decimal places →𝟎.𝟎𝟎𝟎𝟐𝟏𝟔 (f) 𝟏.𝟖 × 𝟏𝟐→1 decimal place →𝟐𝟏.𝟔 Now, we have to answer In which of the cases above is the product less than 1? Looking at the answers, (d) 0.0216 and (e) 0.000216 are less than 1.