24-3x=-27
24+24-3x=-27+24: step 1
-3x=-3: step 2
-3/-3x=-3/-3: step 3
x=1:answer
Answer:
270 miles
Step-by-step explanation:
If she drove 120 miles in 2 hours, that means she drives at 60 miles per hour. 4 hours and 30 minutes can be seen as 4.5, since 30 minutes is half an hour. So then you multiply 60 by 4.5 and get 270.
You first have to turn 4 2/8 and two and 34/8 and then you have to put one over 64 and multiply cross if there is any corrections to make you just have to simplify and do that
Let’s say we have x gallons of brand 1 antifreeze and y gallons of brand 2 antifreeze. We know we need a total of 140 gallons, so one equation to relate the variables would be x+y=140. We also know that our final mixture should have 60% antifreeze, so another equation would be the weighted average of the two brands: .55x+.80y140=.60. (The weighted average is basically multiplying each % (55 and 80) by the number of gallons you have (x and y
) and adding those together, and dividing that by the total number of gallons (140). This equals the % of the final mixture (60).)
Now we have a system of two equations that we can solve.
x+y=140
.55x+.80y140=.60
*rearrange first equation to solve for y
:
y=140−x
*substitute this value in for y
in the second equation:
.55x+.80(140−x)140=.60
*use algebra and solve for x
:
The algebra shouldn’t be too complex, and I’m hoping you’re asking this about the setup rather than the actual algebra, and I’m lazy, and I used a calculator to solve this, and this is probably a long run-on sentence, and I got x=112
.
*plug this in to first equation and solve for y
:
y=140−112=28
x=112,y=28
112 gallons of brand 1 antifreeze, 28 gallons of brand 2 antifreeze. That’s a whole lot of antifreeze.
thanx heyaaaaaa