5.5x Scale
22/4=5.5
She drew the butterfly 5.5 times bigger than it is in real life.
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
Answer:
3
Step-by-step explanation:
f(x) = 2x^2 + 1
f(-1) means that wherever you see an x on the right hand side, you substitute -1.
f(-1) = 2(-1)^2 + 1 = 2 + 1 = 3
15% off
$20 is 100%
$10 is 50%
$1 is 5%
Use that to work them out and voila
