Question 1 - Page 129 - Parity - Chapter 6 Class 7 - Number Play - Ganita Prakash

Transcript

Question 1 - Page 129 Can you figure out which 5 cards add to 30? Is it possible? Now, we know that Odd + Odd = Even Odd + Even = Odd Even + Even = Even We need to add these 5 numbers to be added to get 30, an even number Since all these numbers are odd. Let’s add 5 odd numbers (Odd + Odd) + (Odd + Odd) + Odd = Even + Even + Odd = (Even + Even) + Odd = Even + Odd = Odd Thus, adding 5 odd numbers will always give an odd number Since 30 is an even number, sum 30 is not possible