1) find all pairs of consecutive odd positive integers,both of which are smaller than 18,such that their sum is more than 20.

in this why you took x+ 2 not only x please tell me

let the one number of the pair of positive odd numbers be x therefore other consecutive odd number is (x+2).

both the numbers are smaller than 18.

therefore

thus

sum of two numbers is more than 20.

since x is an odd number.

and

therefore

thus the pair of odd numbers are (11,13) , (13,15) , (15,17)

hope this helps you.

cheers!!

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