Answer:
400cm²
Step-by-step explanation:
the surface area of the sphere =
4/3 x The total surface area of a hemisphere
=> 4/3 x 300 = 400cm²
X = amount of 50% solution
y = total amount after mixing
Note that the amount of alcohol in the 20% solution is 80 (0.2) = 16 oz.
We have 2 unknowns, so we need 2 equations:
first, we can write the equation for the total volume:
y = x + 80
next, apply the percentages to get an equation for the amount of alcohol:
0.4 y = 0.5 x + 16
Finally, solve the pair of equations (in this case, by substitution of the 1st into the second:
0.4 (x + 80) = 0.5x + 16
0.4 x + 32 = 0.5X + 16
rearrange and combine like terms:
0.1x = 16
x = 160
from the 1st equation:
y = 160 + 80 = 240
Knowing she makes $9 for each 1 hour, you know that if you'd need to find how much she made after 4 hours, you would do 9(4), giving you the answer of $36.
With this knowledge, you can replace the 4 with h.
9(h)=P
The reason why it's such a simple equation is because it's per hour and nothing else is being increased, decreased, or changed.
Hope this helps!
Answer:
0.012
Step-by-step explanation:
0.004 * 3 = 0.012
