Question

4. Without actual adding, find sum:
(i) 1 + 3 + 5 + 7 + 9 + 11
(ii) 1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 +17
(iii) 1 + 3 + 5 + 7 + 9+11 + 13 + 15 + 17 + 19 + 21 + 23​

Answer 1

Answer:

1) 6² = 36

2) 9² = 81

3) 12² = 144

Step-by-step explanation:

just count the no. and do square of them.

u can check it using calculator.

AND PLZ MARK ME BRAINLEIST IF I AM CORRECT

Answer 2

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We know that the sum of n odd numbers = n2

(i) 1 + 3 + 5 + 7 + 9 = (5)2 = 25 [∵ n = 5]

(ii) 1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17 + 19 = (10)2 = 100 [∵ n = 10]

(iii) 1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17 + 19 + 21 + 23 = (12)2 = 144 [∵ n = 12]