Answer:
0.14 lb . . . closest choice is 0.11 lb
Step-by-step explanation:
The inside and outside radii are 1/8 in and 3/8 in, respectively. Then the area of the top of the washer is ...
A = π(R² -r²) = π((3/8)² -(1/8)²) = π(9/64 -1/64) = π/8 . . . square inches
The height of the stack of 5 washers will be 5×(1/4 in) = 5/4 in. So, the volume of material in the stack of washers is ...
V = Bh = (π/8)(5/4) = 5π/32 . . . cubic inches
The weight of material is the product of volume and density, so is ...
W = (5π/32 in³)(0.285 lb/in³) ≈ 0.1399 lb ≈ 0.14 lb
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<em>Comment on the question</em>
Since this answer does not correspond to any of the offered choices, we suggest you ask your teacher to work this out for you. We suspect they will have difficulty justifying any of the answer choices shown here. (0.11 lb corresponds to 4 washers, not 5.)
Volume of sphere is given by:
V=4/3πr³
the radius of the sphere will therefore be given by:
5000π=4/3πr³
solving for r we get:
r³=3750
hence
r=15.54 m
the area will therefore be:
A=4πr²
A=4π(15.54)²A=965.49π m²
Answer:
Step-by-step explanation:
Let x be the number of 2 coins and y be the number of 5 coins. Let z be the number of 10 coins she exchanged. Then, we have the first equation

Since she has one 5 coin less than 2 coins, then y=x-1. So we get the equation
which is equivalent to
If we add 5 on both sides and factor out on the right by 5 we get

We can solve for x and get
Since x represents the number of 2 coins, we must have that x is an integer. That is, we cannot have, for example 1.5 2 coins. Since 7 doesn't divide 5, we must have that 7 divides 2z+1. That is, the value of z is such that the number 2z+1 is multiple of 7. That is 2z+1 = 7p where p is an integer.
If that is the case, then
x = 5p, then y = 5p-1. By having 2z+1 = 7p, we are forcing that p is an odd integer, so we have infinite solutions. For each value of p that is an odd integer, then x=5p and y=5p-1 is a solution to the problem
The answer is that he has a 40% chance
10*100=1000
1000/25=40
Making it a 40% chance
1
is the correct answer lol ez stuff