It is asking you to find the sum of k^2 - 1 from k=1 to k=4. Since that is only 4 numbers, calculating the sum by hand wouldn’t be that bad.
(1^2 - 1) + (2^2 - 1) + (3^2 - 1) + (4^2 - 1) = 26
The easier way to find the sum is to use a few simple formulas.
When we have a term that is just a constant c, the formula is c*n.
When we have a variable k, the formula is k*n*(n+1)/2.
When we have a squared variable, the formula is k*n*(n+1)*(2n+1)/6.
In this case, we have a squared variable k^2 and a constant of -1.
So plug in n=4 to the formulas:
4*5*9/6 - 1*4 = 26
The answer is 26
Answer=15:39
Step1(find the number of right handed batters)
Left-handed batters=45
5 45
__=___
8 x
Cross multiply
5x=360
divide both sides by 5
x=72
Right-handed batters=72
Step 2 (find the number of total batters)
total batters=45+72=117
Step3 (find the ratio of left handed batters to total batters)
Left-handed batters to total batters= 45/117
45/117 can be shortened to 15/39
Answer=15:39
So ur going from a smaller shape to a larger shape....means the scale factor is more then 1. The scale factor is the number that u multiply the original shape by to get the other shape.
so lets look at DE...it is 2.....and D'E' is 6
so 2 * x = 6...with ur scale factor being x
2x = 6
x = 6/2
x = 3.....so the scale factor is 3....because multiplying the original shape by 3, gives u the other shape
Answer: Area of a right circular Cylinder--- curved surface area -2πrh Total surface area -2πr(r+h),where 'r' is the radius of the circular surface and 'h' is the height of the cylinder.
