Answer:
0.26 and 0.577
Step-by-step explanation:
Given :
x :___0 ___ 1 ____ 2 ____ 3
f(x):_0.80 _0.15__0.04 __0.01
The mean :
E(X) = Σ(x * p(x))
E(X) = (0*0.8) + (1*0.15) + (2*0.04) + (3*0.01)
E(X) = 0 + 0.15 + 0.08 + 0.03
E(X) = 0.26
Var(X) = Σx²*p(x)) - E(x)²
Σx²*p(x)) = (0^2*0.8) + (1^2*0.15) + (2^2*0.04) + (3^2*0.01) = 0.4
Σx²*p(x)) - E(x)² = 0.4 - 0.26² = 0.3324
Std(X) = √0.334 = 0.577
Answer:
- The sequence of transformations that maps triangle XYZ onto triangle X"Y"Z" is <u>translation 5 units to the left, followed by translation 1 unit down, and relfection accross the x-axis</u>.
Explanation:
By inspection (watching the figure), you can tell that to transform the triangle XY onto triangle X"Y"Z", you must slide the former 5 units to the left, 1 unit down, and, finally, reflect it across the x-axys.
You can check that analitically
Departing from the triangle: XYZ
- <u>Translation 5 units to the left</u>: (x,y) → (x - 5, y)
- Vertex X: (-6,2) → (-6 - 5, 2) = (-11,2)
- Vertex Y: (-4, 7) → (-4 - 5, 7) = (-9,7)
- Vertex Z: (-2, 2) → (-2 -5, 2) = (-7, 2)
- <u>Translation 1 unit down</u>: (x,y) → (x, y-1)
- (-11,2) → (-11, 2 - 1) = (-11, 1)
- (-9,7) → (-9, 7 - 1) = (-9, 6)
- (-7, 2) → (-7, 2 - 1) = (-7, 1)
- <u>Reflextion accross the x-axis</u>: (x,y) → (x, -y)
- (-11, 1) → (-11, -1), which are the coordinates of vertex X"
- (-9, 6) → (-9, -6), which are the coordinates of vertex Y""
- (-7, 1) → (-7, -1), which are the coordinates of vertex Z"
Thus, in conclusion, it is proved that the sequence of transformations that maps triangle XYZ onto triangle X"Y"Z" is translation 5 units to the left, followed by translation 1 unit down, and relfection accross the x-axis.
<span>Cada goma de borrar es $ 5. Primero restar el precio de las revistas ($ 5) del dinero que gastó. Ella ahora tiene $ 20. Luego divida eso entre cuantos borradores compró (4). 20 dividido por 4 es 5. Cada borrador fue de $ 5. ¡Espero que la traducción tenga sentido !!</span>
One company wants $10 per 3.5 hours, so they want 10 / 3.5 ≈ 2,86 dollars per hour (after rounding to the closest hundreths).
Second company wants $1.25 per half an hour, so they want 2 * 1,25 = 2,50 dollars per hour.
The unit rate is 2,86:2,50
