Can someone give me the formula to calculate the numbers of balls in a pyramid ?
83297
Each level has the next highest square number of balls so:\n\n1 + 2^2 + 3^2 + ... + 99^2 + 100^2\n\nThe formula for the sum of the first n squares is:\nn (n+1) *(n + 1/2)/ 3 \n\nIn this case n = 100 so:\n100(101)(100.5/3)=3383500
223583
If you are looking for the surface area or volume of a pyramid, check this out:
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180  (187 balls)\n\n@ 1:14 AM IST
160337
square-based pyramid=\n1 squared base\n4 triangle shaped sides\n1 point at the top of the shape\n4 more at the bottom
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Use the FOIL method; First, Outer, Inner, Last.\n\nFirst, n * n\n\nOuter, n * 5\n\nInner, n * 7\n\nLast 7 * 5.\n\nThen add them all together.\n\n22 NOV 06, 0420 hrs, GMT.
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Make a tree that shows all possibilities you have.\nOn the first level there is the choice of the box with 0.5 probability each. On the next level, box A, you have two choices again, with the prob. is 3/7 to find a red ball, 4/7 to find a white ball, etc.\n\nWhen you have finished to tree, use it to make a list and\ncalculate the prob. for picking red-red, red-white, etc.
10703
Volume of a pyramid = (1/3)(area of base, which is a square) * height\nSo 30cm^3 = (1/3) (s^2)(h) Multiply by 3 to clear the fraction --> \n90cm^2 = s^2(h)\n\nNow the problem is that we have one equation for two unknowns. We cannot arrive at one definite solution because there are infinite possibilities. \nSo we can get some possible dimensions by assigning a value to one dimension and then working out the other one. \n\nFor example, if the sides of the botom are 1 cm, then the height is 90\nIf the sides are each 3, then the area of the base is 9 and the height is 10.
15239
The correct answer is 190. It would involve any spare (all pins down on two balls) in the first frame, then single-pin spare conversions in frames 2-9 and a 9-count, spare and another 9-count in the tenth and final frame.
704007
use arithmatic progression formula n(2a+(n-1)d)/2\nwhere n=no. of terms. a=value of first term and d=common difference between each consecutive term\nsay fro your first eg. no. of black ball = 1+3+5+...\nn=10 a=1 d=2\nso sum = 10(2+9*2)/2 = 100\nsolve the rest by changing values of n, a and other variables respectively
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The Lourve pyramid is made of 4 triangles and a square base.\nSo the surface area of this pyramid\n= 4*(b*h)/2 + l^2\n= 2lh + l^2\nwhere the base of the triangle, b = length of a side of the square and h is the perpendicular height of the triangle.\n\nVolume = (1/3)(base area)(height)
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Ask the magic 8-ball\n\nhttp://www.indra.com/8ball/
63817
tsniperx\n2 months ago\n\nVolume of one block cube = 10cm*10cm*10cm = 1000cm^3\nVolume of two block cube = 2000 cm^3\nVolume of one sphere = (4/3)*pi*r^3 = (4/3)*pi*(5cm)^3\nVolume of one sphere= 523.59877 cm^3\n\nno spheres= Volume of clay / Volume of sphere= 2000cm^3 / 523.59877cm^3\nNo spheres must be integer = 3 spheres
766854
28! I just did it on paper putting 8 dots and connecting each one with the rest. There is a math formula for it but I don't remember it!
885043
I have no pool table but this is easily answered from the memories of my mis-spent youth. I spent hours upon hours in smoke filled pool rooms as a boy.\n\nThere are 15 balls in a full rack. 1 thru 7 all have the white circle in the middle. These balls are refered to as solids.\n\nThe 9 ball thru the 15 all have a colored stripe passing around a white ball. These  balls are called stripes. \n\nThe eight ball looks like a solid ball but in some games it belongs to neither group. it is it's own ball.\n\nFew people know that the 1 and 9 are the same color. This pattern repeats itself throughout the set. I will list the colors and numbers, just remember all balls above eight are stripes, no white circle.\n\n1&9 yellow\n2&10 blue\n3&11 Red\n4&12 Purple\n5&13 Orange\n6&14 Green\n7&15 Maroon\n8 Black
106436
I followed bugzpodder's advice.  Here's the formula I came up with. \n\n - 778728 - 121373345554191121 / 217945728000 * n^4 + 1298728131310487 / 1009008000 * n^3 + 670835515657 / 360360 * n + 2210058967013 / 12830400 * n^5 - 113499324114761 / 2874009600 * n^6 + 8961501223669 / 1306368000 * n^7 - 66868104743317 / 73156608000 * n^8 + 85853565361 / 914457600 * n^9 - 121097474346419 / 60540480 * n^2 - 27139677827 / 3657830400 * n^10 + 1792199 / 4009500 * n^11 - 1158076427 / 57480192000 * n^12 + 12283303 / 18681062400 * n^13 - 7672127 / 523069747200 * n^14 + 261523 / 1307674368000 * n^15 - 13147 / 10461394944000 * n^16\n\nCheers
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http://mathworld.wolfram.com/SieveofEratosthenes.html
615446
There will be 325 marbles in the 25th row.\nSolution- As we move a layer(downward)the number of marbles in that row will get added to its consecutive number(keeping in vie ho much has been added before).For eg-\nif the 1st row has 1 marble,the 2nd row will have 1+2=3 marbles.Similarly, the third row will have 3+3=6.The third row will have 6+4=10, 5th row-10+5=15 and so on.....