How do you find two consecutive odd integers whose sum is 196?

2 Answers
Apr 25, 2016

97 and 99

Explanation:

There is at least two ways of doing this: This is my approach

color(blue)("Step 1") Define a number so that it is always even

" "Let n be any number then 2n is always even.

color(blue)("Step 2") Modify the defined number so that the result is always odd

" "If 2n is always even then 2n+1 is always odd
'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Let the first odd number be 2n+1
Then the second odd number is (2n+1)+2=2n+3

Thus our given condition is such that:

(2n+1)+(2n+3)=196

=>4n+4=196

Subtract 4 from both sides

=>4n=192

Divide both sides by 4

=>n=192/4=48

But the first number is 2n+1 = 2(48)+1 = 97

So the second number is 97+2=99
'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Check: 97+99= 196

Apr 25, 2016

Another way

Explanation:

Let the first number be n
Let the second number be n+2

Then n+n+2=196

2n+2=196

Subtract 2 from both sides

2n=194

Divide both sides by 2

n=194/2= 97

The first number is 97 so the second is 97+2=99

color(red)("Notice that the " 2n + 2" is of the same format as that in my")color(red)("other solution of "4n+4)