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.
(4,-3) does not pass through the graph
If you put (4, -3) into the equation you get 18
If you put (4/3, -1) into the equation you get 6
If you put (-2, -6) into the equation you get 6
Answer:

Step-by-step explanation:



because 16 is a perfect square root and it splits into 4 * 4 while 10 isnt a perfect square root so it stays inside.
Answer:
8 / 15
Step-by-step explanation:
By Pythagoras theorem,
OP² + PQ² = OQ²
OP² + 8² = 17²
OP² = 17² - 8²
= 289- 64
OP² = 225
OP² = 15²
OP = 15
Formula : -
Tan θ = Opposite side / Adjacent side
Here,
θ = Q
Opposite side = PQ = 8
Adjacent side = OP = 15
Tan Q = 8 / 15
1 figure = $17 so you multiply 4 and 17 to get 68
Martin will need to save $68