SOLUTION: what consecutive numbers if we add we will get 945

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Question 259976: what consecutive numbers if we add we will get 945
Found 2 solutions by mananth, Edwin McCravy:
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
Let one number be x
Then the next consecutive number will be x+1
The sum of x and x+1 is 945
x+ x+1 = 945
2x+1=945
2x= 945-1=944
x=944/2
x= 472
The numbers are 472 and 473

Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!

That depends on how many consecutive integers you 
want to add to get 945. You forgot to tell us how 
many integers.  

For instance, is you had told us you wanted 10 consecutive integers
which have sum 945, we could have shown you how to find them.  
They would be

90+91+92+93+94+95+96+97+98+99 = 945

And, say, if you had told us the you wanted 18, then we'd
have said to start at 44

44+45+46+47+48+49+50+51+52+53+54+55+56+57+58+59+60+61=945

And, say, if you had told us the you wanted only 5 or 6, then we'd
have said to start at 187 if you wanted 5, and with 155 if you
had wanted 6

187+188+189+190+191=945

or with 6

155+156+157+158+159+160=945

or with just 2 consecutive integers, as the other tutor
assumed, it would be:

472+473=945.

We'd have use the equation

+S%5Bn%5D=+%28n++%28+2a%5B1%5D%2B%28n-1%29d+%29+%29%2F2++

Suppose I had wanted to find five consecutive integers
whose sum is 945:

187+188+189+190+191=945

but didn't know I was supposed to start at 187.  Here's
how I'd know to start at 187:  I'd substitute n=5
S%5B5%5D=945

and n=5 and d=1 because the difference between
any two consecutive integers is 1.

S%5Bn%5D=n%282a%5B1%5D%2B%28n-1%29d%29%2F2

S%5B5%5D=5%282a%5B1%5D%2B%285-1%29%281%29%29%2F2

945=5%282a%5B1%5D%2B4%29%2F2

Multiply both sides by 2 to clear of fractions:

1890=5%282a%5B1%5D%2B4%29

Divide both sides by 5

378=2a%5B1%5D%2B4

Subtract 4 from both sides

374=2a%5B1%5D

Then divide both sides by 2, and we'd have

187=a%5B1%5D

Then we'd have known to start at 187.

Next time you post on here, be sure to give all
the information and to tell us exactly what you 
want to find.

Edwin