Try this:
1) note that weight of pure antifreeze before mixing and after mixing is the same. So, if 'x' is weight of pure antifreeze in 50% solution, it is possible to make up equation before mixing: 0.5x+0.2*90.
2) there are 0.2*90=18 gal. of pure antifreeze in the 20% solution. If 'x' gal. is the weight of pure antifreeze in 50% sol. and 18 gal. is the weight of pure antifreeze in 20% sol., it is possible to make up an equation after mixing: 0.4(x+18).
3) using the both parts: 0.5x+0.2*90=0.4(x+18) ⇒ x=54 gal. of <u>pure</u> weight.
4) to find 50% solution of 54 gal. pure weight just 54:0.5=108 gal.
Answer: 108 gal.
Answer:
The answer is B. $3.85.
Step-by-step explanation:
This is because, first if we get the percentage that the shoes were marked up by, we get that they were marked up to $35, because 40% of $25 is $10 and $25 + $10 = $35.
Then, we find the percentage of $35 that she earned. In order to do this, we see what 11% of $35 is. We get $3.85, because 10% of $35 is $3.50, and 1% of $35 is $0.35. $3.50 + $0.35 = $3.85.
This is why the answer is B. $3.85.
You'll want to use the quadratic formula:
-b (+/-) sqrt(b^2 - 4ac), all divided by 2a.
Under the square root you'll get:
-11
remember that the square root of -1 is i.
sqrt(-11) can be factored to sqrt(11*-1) and then sqrt(-1) * sqrt(11)
which becomes i*sqrt(11)
so your complex solution is:
-3 (+/-) (i*sqrt(11)), all over 4
Answer:
-1 6/8
Step-by-step explanation: