This question seems to have way too much information and be more confusing then it needs to be. When it comes down to it the only important information is that
<span>>The store manager decides to charge a weekly fee of $6
></span><span>Books to students for $2 per book
And the question is
></span><span>This
is a decision (fair or unfair) for the students as they will pay (more
than,the same as, less than) they would pay to rent four books.
Answer:
(I think) the decision is fair for the students as they will pay less than they would pay to rent four books.
</span>
42 12
—- = —-
56 x
Simplified:
3 12
— = —-
4 x
Multiply both sides by 4:
3 = 48
—-
x
Multiply both sides by x:
3x = 48
Divide both sides by 3:
x = 16
First lets write down our starting conditions:
we have 22 gallons and it has 16% of ammonia
16% of 22 gallons is
A = 16/100*22 = 3,52 gallons
Now since only watter is evaporating that means that in second scenario after some watter evaporated there is still 3,52 gallons of ammonia. But now those 3,52 gallons of ammonia represent 24% of total mixture. So now we go other way.
24 % is 3,52 gallons
100% is x gallons
x = 100/24*3,52 = 14.667 gallons
That means that he has to evaporate
22 - 14.6667 = 7,333 gallons of water.
Let
x--------> <span>the rectangle's length
y-------> </span><span>the rectangle's width
we now that
Area of rectangle=x*y
Area=256 cm</span>²
<span>256=x*y-------> equation 1
y=4x-48------> y=4x-48------> equation 2
substitute equation 2 in equation 1
256=x*[4x-48]-----> 256=4x</span>²-48x
4x²-48x-256=0
<span>
using a graph tool----> to resolve the second order equation
see the attached figure
the solution is
x=16 cm
y=4x-48----> y=4*16-48-----> y=16 cm
is a square
the answer is</span>
the rectangle's length is 16 cm