Answer:
Expected time is 15 hours for him to get to safety.
Step-by-step explanation:
We define X as the time that this miner would get to safety.
We define Y as the door he chooses initially.
P(Y= 1) = P(Y=2)=P(Y=3) = 1/3
We have E[X|Y=1] = 3
E[X|Y] = 5 hours + E[X}
E[X|Y] = 7 hours + E[X]
Then we have
E[X] = 1/3(3 + 5 + E[X] + 7 + E[X])
We cross multiply
3*E[X] = (15 + 2E[x])
3E[X] - 2E[X] = 15
E[X] = 15
So the time it would take to get him to safety is 15 hours
Answer:
a. 122 degree is the answer
Answer:
3y +22
Step-by-step explanation:
y + 6 + 2(y + 8)
Distribute the 2
y+6+2y+16
Combine like terms
3y +22
The question in English
<span>1 Determine the length and area of a circle whose measures are:
a) radius 11cm b) radius 4.2 cm c) diameter 42.3 cm
2 considering that a large traditional pizza is 36 cm in radius and a small traditional pizza has 26 cm.Determine the difference between the area of the two pizzas
3.a worker spends 3 hours to clear a circular terrain of 6 meters radius. If the terrain was 12 meters radius, how much time would the worker spend to clean such terrain ???
4, transform the following arcs into radians
a) 27 ° b) 81 ° c) 144 ° d) 225 ° d) 315 °
Part 1)
we know that
length of a circle is equal to the circumference
circumference=2*pi*r
area of the circle=pi*r²
part a ) radius 11 cm
</span><span>circumference=2*pi*11-----> 69.08 cm
area of the circle=pi*11²----> 379.94 cm²
</span>
<span><span>part b) radius 4.2 cm
</span><span>circumference=2*pi*4.2-----> 26.38 cm
area of the circle=pi*4.2²----> 55.39 cm²
</span></span>
<span><span>part c ) diameter 42.3 cm
radius r=42.3/2=21.15 cm
</span><span>circumference=2*pi*21.15-----> 132.82 cm
area of the circle=pi*21.15²----> 1404.59 cm²
Part 2)
</span></span>
<span>area large traditional pizza
r=36 cm
area=pi*36²----> 4069.44 cm²
area </span><span>small traditional pizza
r=26 cm
area=pi*26²-----> 2122.64 cm²
</span><span>difference between the area of the two pizzas
=4069.44-2122.64
difference </span><span>between the area of the two pizzas=1946.80 cm²
Part 3)
Area of the </span><span>circular terrain of 6 meters radius
area=pi*6²-----> 113.04 m²
</span><span>Area of the <span>circular terrain of 12 meters radius
area=pi*12²-----> 452.16 m²
</span></span>
if a <span>worker spends 3 hours to clear a circular terrain of--------> 113.04 m²
x hours---------------------------> 452.16 m²
x=452.16*3/113.04-----> x=12 hours
Part 4) </span><span>transform the following arcs into radians
a) 27°
pi radians------> 180°
x radians-----> 27°
x=27*pi/180-----> x=0.15*pi radians------> 0.47 radians
</span><span>b) 81°
pi radians------> 180°
x radians-----> 81°
x=81*pi/180-----> x=0.45*pi radians------> 1.41 radians
</span>
<span>c) 144°
pi radians------> 180°
x radians-----> 144°
x=144*pi/180-----> x=0.80*pi radians------> 2.51 radians
</span>
<span>d) 225°
pi radians------> 180°
x radians-----> 225°
x=225*pi/180-----> x=1.25*pi radians------> 3.93 radians
</span>
<span>e) 315°
pi radians------> 180°
x radians-----> 315°
x=315*pi/180-----> x=1.75*pi radians------> 5.50 radians
</span><span>
the answer in Portuguese
</span>
<span>Parte 1)
</span>
<span>nós sabemos isso
</span><span>comprimento de um círculo é igual à circunferência
</span><span>circunferência=2*pi*r
</span>área do círculo<span>=pi*r²
parte a )
</span>raio<span> 11 cm
</span><span>circunferência=2*pi*11-----> 69.08 cm
</span><span><span>área do círculo=pi*11²----> 379.94 cm²
</span>
<span>parte b) raio 4.2 cm
</span></span><span>circunferência=2*pi*4.2-----> 26.38 cm
</span><span><span>área do círculo=pi*4.2²----> 55.39 cm²
</span>
<span>parte c )
</span></span>diâmetro<span> 42.3 cm
</span><span>raio r=42.3/2=21.15 cm
</span><span>circunferência=2*pi*21.15-----> 132.82 cm
</span><span><span>área do círculo=pi*21.15²----> 1404.59 cm²
Parte 2)
</span>
</span>
área grande pizza tradicional<span>r=36 cm
</span><span>área=pi*36²----> 4069.44 cm²
</span>
<span>área pequena pizza tradicional<span>
r=26 cm
</span></span><span>área=pi*26²-----> 2122.64 cm²
</span>diferença entre a área das duas pizzas<span> =4069.44-2122.64
</span>diferença entre a área das duas pizzas<span>=1946.80 cm²
Parte 3)
</span><span><span>
Área do terreno circular de 6 metros de raio</span>
</span><span>área=pi*6²-----> 113.04 m²
</span>
<span>Área do terreno circular de 12 metros de raio
</span><span><span>área=pi*12²-----> 452.16 m²
</span>
</span>se um trabalhador gastar 3 horas para limpar um terreno <span>-----> 113.04 m²
x hours---------------------------> 452.16 m²
x=452.16*3/113.04-----> x=12 horas
Parte 4) </span><span><span>transformar os seguintes arcos em radianos
a) 27°
pi radianos------> 180°
x radianos-----> 27°
x=27*pi/180-----> x=0.15*pi radianos------> 0.47 radianos
</span><span>b) 81°
pi radianos------> 180°
x radianos-----> 81°
x=81*pi/180-----> x=0.45*pi radianos------> 1.41 radianos
</span>
<span>c) 144°
pi radianos------> 180°
x radianos-----> 144°
x=144*pi/180-----> x=0.80*pi radianos------> 2.51 radianos
</span>
<span>d) 225°
pi radianos------> 180°
x radianos-----> 225°
x=225*pi/180-----> x=1.25*pi radianos------> 3.93 radianos
</span>
<span>e) 315°
pi radianos------> 180°
x radianos-----> 315°
x=315*pi/180-----> x=1.75*pi radianos------> 5.50 radianos</span></span>
B Bc it’s a right triangle meaning it’s 90 degrees so 90-10 is 80 and 80 divided by 2 is 40
