1+3=4
1+3+5=9
1+3+5+7=16
notice it goes like this:
first two = 2^2
first three=3^3
first four= 4^2
first 15=15^2
first hundred= ???
Sum the first two odd numbers, then the first three, the first four, and so on. From these observations could you guess the sum of the first 100 odd numbers?
3 answers
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