Gauss' method for addition relies on the fact that you can 'pair' certain numbers together. Look at the example:
1+2+3+4+5+6+7+8+9+10
We could manually add all these together from left to right but a clever way to think about this is if we add together the ends of the sum (10+1) we get 11. If we then move one in from the ends and add these (2+9) we also get 11. This means that 1+2+...+9+10 is the same as 11+11+...+11+11.
Because each 2 numbers adds to 11 we know the total number of 11's we have to add together is the length of the sum divided by 2. In our case 5 (10 ÷ 2). We need to add 5 lots of 11 to get our answer. This is the same as 11 × 5 which is easily seen to be 55.
(If you add the 10 numbers together on a calculator you'll see 1+2+3+4+5+6+7+8+9+10 = 55) so this method really makes it a lot quicker.
Looking at your sequence, if we pair the ends together we get 401 (400+1) and we multiply this by the length of the sequence divided by 2. In your case, 200 (400 ÷ 2).
So the sum of all the numbers from 1 to 400 must be 401 × 200 = 80,200.
Remember the steps:
1. Pair the ends together and add them
2. Times this number by the length of the sequence halved
Hope this helps.
By my calculations and understanding into this problem I have figured out the answer to this thing and it is very simple and easy enough to actually say it so I can type it out instead because I can’t say anything on this thing even though I’m doing a voice record and I don’t even know how my grandma is doing right now so I’m just blah bling around is it random words of mine but honestly I would love to explain and tell you the answer but I do not know how to type it out so I’m just going to say it like I just said two seconds ago but I didn’t really say it again I just typed it I don’t know I keep getting confused with that but anyways the answer is very easy
Answer:
B.
Step-by-step explanation:
so 8*5 is 40 which leaves 39 points to be accounted for.
39/3 is 13 (easy questions)
8+13=21 which is the amount of questions Chantrea answered correctly so yee
25m+100−24m−75=68
Step 1: Simplify both sides of the equation.
25m+100−24m−75=68
25m+100+−24m+−75=68
(25m+−24m)+(100+−75)=68(Combine Like Terms)
m+25=68
m+25=68
Step 2: Subtract 25 from both sides.
m+25−25=68−25
m=43
Answer:
m=43
Answer:
the answer would be 180 degrees
Hope this helps :)
Step-by-step explanation:
