Question

The sum of seven odd consecutive is 217. Find the middle number

Answer 1

Answer:

x + x+1 + x+2 + x+3 + x+4 + x+5 + x+6 =217

7x+21=217

7x=196

x=28

Middle Number will be:

x+3

28+3

=31

Therefore, the middle number is 31.

Step-by-step explanation:

Answer 2

Answer:

31

Step-by-step explanation:

Let's put this into equation form.

n + (n + 1) + (n+2) + (n+3) + (n+4) + (n + 5) + (n+6) = 217

Each number is increasingly getting farther away from n (the first number) by 1.

If we simplify, by adding all of the numbers and the n's. We get:

7n + 21 = 217

Let's subtract 21 from both sides to start the process of isolating x.

7n = 196

Now we can divide both sides by 7, to isolate x.

n = 28.

That looks like the answer, but it is not. Remember n is the first number, we want the middle, which out of 7 is the 4th number.

The 4th number is equal to (n+3) or (28 + 3)

The 4th number is 31.

Let's check if this is correct.

28 + 29 + 30 + 31 + 32 + 33 + 34 = 217.

The problem is complete.