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Question 2 - Figure it out - Page 131 - Chapter 6 Class 7 - Number Play - Ganita Prakash
Last updated at October 16, 2025 by Teachoo
Class 7 (Ganita Prakash 1, 2 & old NCERT)
Chapter 6 Class 7 - Number Play - Ganita Prakash
- Numbers can Tell us Things, Supercells
- Parity
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Figure it out - Page 131
- Small Squares in Grids (Parity in Multiplication)
- Parity of Expressions
- Some Explorations in Grids
- Magic Square
- Figure it out - Page 136
- Generalising 3 × 3 Magic Square
- First ever 4 × 4 Magic Square
- Magic Squares in History and Culture
- Virahāṅka Fibonacci Numbers
- Digits in Disguise
- Figure it out - Page 143, 144
Transcript
Question 2 Lakpa has an odd number of ₹1 coins, an odd number of ₹5 coins and an even number of ₹10 coins in his piggy bank. He calculated the total and got ₹205. Did he make a mistake? If he did, explain why. If he didn’t, how many coins of each type could he have? Let’s solve this one by one Value of ₹1 coins He has an odd number of ₹1 coins Since ₹1 is an odd value Now, Total value = Odd number × Odd value = Odd Value of ₹5 coins He has an odd number of ₹5 coins Since ₹5 is an odd value Now, Total value = Odd number × Odd value = Odd Value of ₹10 coins He has an even number of ₹10 coins Since ₹10 is an even value Now, Total value = Even number × Even value = Even Total sum To find the total amount, we add the values: Odd + Odd + Even = (Odd + Odd) + Even = Even + Even = Even Thus, total sum of money in his piggy bank must be an even number. Since ₹205 is an odd number, his calculation is incorrect.
