Letter b
Angles are supplementary ( the sum of both angles =180)
11x + 8 + 12x +11 = 180
23 x = 180 - 19
23x -= 161
X = 7
Hey there! I'm happy to help!
Let's have the capacity be c. The tank is currently at 4/5c. We subtract 190 and then we are at 1/6c. Let's set this up as an equation and solve it.
4/5c-190=1/6c
We want to get the c all by itself to see the capacity of the tank. Let's get all of the c values on the left side of the equation and the numbers on the right by using inverse operations.
4/5c-190=1/6c
Add 190 to both sides.
4/5c=1/6+190
Subtract 1/6 from both sides.
19/30c=190
Divide both sides by 19/30.
c=300
So, the capacity of the tank is 300 liters of water.
Have a wonderful day and keep on learning! :D
Answer:
Proper fraction
Step-by-step explanation:
If the numerator is less than the denominator , then it is proper fraction.
Example : 
Answer:
1240.4 mm²
Step-by-step explanation:
The surface area of a pyramid = Area of the all sides + Area of base
Each side is a triangle.
With a regular pentagonal pyramid, the area of each triangle is

For the 5 triangles,

Substituting given values,

Area of base = 440.4 mm²
Surface area of a pyramid = 800 + 440.4 mm² = 1240.4 mm²
Three hundred ten million, seven hundred sixty three thousand, one hundred thirty six