Question 1187361: The human body contains approx. 30 trillion red blood cells. If these cells were placed tightly together, they would fit into a cube approx. 5 in. on each edge.
1) Determine outside surface of cube in sq. yds.
2)If the outside surface of cube was divided into 30 trillion pieces, determine outside surface in sq. yds.
Unsure how to solve.
Found 3 solutions by Alan3354, KMST, Theo:
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! The human body contains approx. 30 trillion red blood cells. If these cells were placed tightly together, they would fit into a cube approx. 5 in. on each edge.
1) Determine outside surface of cube in sq. yds.
The surface area is 6s^2 = 6*25 sq inches.
1 yard = 36 inches
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2)If the outside surface of cube was divided into 30 trillion pieces, determine outside surface in sq. yds.
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There's no inside surface area, so what does "outside surface area" mean?
Divide the SA by 30,000,000,000,000.
Answer by KMST(5328)  (Show Source):
You can put this solution on YOUR website! Strange problem.
 in the USA
(Between different countries, we do not agree on the definitions of billion, trillion, trapezoid, pavement, pants, hood, trunk, engine, and other terms).
A cube with  edges has an outside surface area of
If that outside surface area was divided into
 pieces of equal area,
each piece would have an area of
 =  =
= =
Hopefully, that is an acceptable answer, and there is no objection to having 3 significant figures in the result.
Otherwise, maybe  , with 2 significant figures, may be the expected answer, since 30 trillion appears to have 2 significant figures.
Answer by Theo(13342)  (Show Source):
You can put this solution on YOUR website! the cube measures 5 inches on each edge.
the volume of the cube is equal to 5^3 cubic inches = 125 cubic inches.
the surface area of the cube is equal to 6 * 5^3 square inches = 150 square inches.
there are 12 inches to a foot.
there are 36 inches to a yard (3 feet * 12 = 36 inches).
if you take inches and divide them by 36, you get yards.
if you take square inches and divide them by 36^2, you get square yards.
if you take cubic inches and divide them by 36^3, you get cubic yards.
the volume = 125 cubic inches divided by 36^3 = .0026791830 cubic yards.
the surface area = 6 * 25 = 125 square inches divided by 36^2 = .1157407407.
the cube holds 30 trillion red blood cells.
that is equal to 30 * 10^12 red blood cells.
that's the volume of the cube in numbers of red blood cells.
since the volume of the cube is equal to one edge cubed, then each edge contains the cube root of 30 * 10^6 red blood cells.
simplify that to get 31,072.32506 red blood cells per edge.
since the surface area of the cube is equal to 6 * one edge squared, then the surface area of the cube contains 6 * 31072.32506^2 = 5,792,936,308 red blood cells.
that should be everything i can calculate for the cube, except, perhaps, the ratio of red blood cells to yards.
we have one edge is equal to 5 inches which is equal to 31,072.32506 red blood cells
take that and divide it by 5 and you get 6214.465012 red blood cells per inch.
since 1 inch / 36 = /.02777777..... yards, then you get:
6214.465012 / .0277777.... = . 223720.7404 red blood cells per yard.
we know from above that the volume of the cube is equal to .0026791830 cubic yards.
1 cubic yard is equal to 223720.7402^3 = 1.119744 * 10^16 red blood cells.
multiply that by .0026791830 to get a volume of 3 * 10^13 = 30 trillion red blood cells.
the figures work out (painfully, i might add), but they now look good.
best i can do.
take what you can and let me know if you have any further questions.
theo
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