In an answer the exponent can't be negative
Answer:
.1 approx.
Step-by-step explanation:
5/60 and x/100%
Cross multiplying...
5 x 100% = 5
5/60 ~= .1
( I dunno if I am right, so please check first.)
I don't know what the "six-step method" is supposed to be, so I'll just demonstrate the typical method for this problem.
Let <em>x</em> be the amount (in gal) of the 50% antifreeze solution that is required. The new solution will then have a total volume of (<em>x</em> + 60) gal.
Each gal of the 50% solution used contributes 0.5 gal of antifreeze. Similarly, each gal of the 30% solution contributes 0.3 gal of antifreeze. So the new solution will contain (0.5 <em>x</em> + 0.3 * 60) gal = (0.5 <em>x</em> + 18) gal of antifreeze.
We want the concentration of antifreeze to be 40% in the new solution, so we need to have
(0.5 <em>x</em> + 18) / (<em>x</em> + 60) = 0.4
Solve for <em>x</em> :
0.5 <em>x</em> + 18 = 0.4 (<em>x</em> + 60)
0.5 <em>x</em> + 18 = 0.4 <em>x</em> + 24
0.5 <em>x</em> - 0.4 <em>x</em> = 24 - 18
0.1 <em>x</em> = 6
<em>x</em> = 6/0.1 = 60 gal
Answer: With 11 pipes, you need 31.82 minutes to fill the tank.
Step-by-step explanation:
Let's define R as the rate at which one single pipe can fill a tank.
We know that 7 of them can fill a tank in 50 minutes, then we have the equation:
7*R*50min = 1 tank
Whit this equation, we can find the value of R:
R = 1 tank/(7*50min) = (1/350) tank/min.
Now that we know the value of R, we can do the same calculation but now with 11 pipes.
Then the time needed to fill the tank, T, is such that:
11*(1/350 tank/min)*T = 1 tank
We need to isolate T.
T = 1 tank/(11*(1/350 tank/min)) = 31.82 min
With 11 pipes, you need 31.82 minutes to fill the tank.
1/5 = 3/15
1/3 = 5/15
2/3 = 10/15
So no :)
Reason why:
You want to find the common denominator between all three fractions, so all fractions are the same proportions. So in this case, if you multiply 5*3 you get 15, making it the common denominator. Then since you multiplied the 5 in 1/5 by 3 to get 15, and you have to multiply the 3 in 1/3 and 2/3 by 5 to get 15, then you multiply the numerator by the same number.
Sorry I am terrible at explaining things. Hope this helped though!
