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.)
Whenever a problem says "one number" and "another number" we can substitute x and y. for this we have x=2y+1 and xy=1. since we know the value of x (2y+1) we can substitute it for the other equation to get (2y+1)y=10. simplify to get 2y^2+y=10. from here you can do a few methods to solve this, but the simplest in my opinion is by factoring.
In order to factor it must be equal to 0, so we have 2y^2+y-10=0. We factor this and get y=5 (we also get y=-4 but it is an extraneous root). now we can plug that into either equation and find that x=2.
this means our two numbers are 5 and 2
You can find the simplest form of 120/180 by rounding down the numbers. you can take the zeros away and your left with 12/18. you can make it even smaller by using the 6 time tables. 12 and 18 are both in the 6 time tables. 2×6=12 and 3×6=18. The answer is 2/3.
Hope I helped :D
Answer:
40 degrees
Step-by-step explanation:
The sum of the angles is 180.
A 100 degree angle cannot be a base angle because then
the sum of the base angles would be 200 degrees.
The 100 must be the vertex angle.
Equation:
x + x + 100 = 180
2x = 80
x = 40 degrees.
Each of the base angles is 40 degrees.
