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.
Answer:
Option F. 1/√3
Step-by-step explanation:
From the question given above, the following data were obtained:
Angle θ = 30°
Opposite = 1
Adjacent = √3
The value of Tan 30° can be obtained as illustrated below:
Tan θ = Opposite / Adjacent
Tan 30 = 1/√3
Thus, the value of Tan 30° is 1/√3
Im taking this to mean (2 x^7 y)^2 (y^5)^3
= 4x^14 y^2 * y^15
= 4x^14 y^17 which is option 4
Answer:
x = 7
Step-by-step explanation:
123 = 17x + 4
123 - 4 = 17x
119 = 17x
119 / 17 = x
7 = x
Answer:
6 square units
Step-by-step explanation:
Given shape is of a trapezoid:
Area of shape = area of square + area of triangle
