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
If we know that she got 75%, we can write it as the fraction 75/100.
We also know that she got 60 correct out of an unknown number of questions, which we can call 'x'
We means we know that 75/100 = 60/x (the number of questions)
Cross multiply to get an equation.
75 * x=60 * 100 -----> 75x=6000
Divide both sides by 75 to solve for x.
6000/75=80
x=80, meaning that her test had 80 questions on it.
Answer: A. 14 miles each day.
Step-by-step explanation:
Day 1 : 15 miles
Day 2 : 10 miles
Day 3 : 7 miles
15 + 10 + 7 = 32 miles
60 - 32 = 28 miles
2 days left
28/2 = 14
14 is less than 18
Answer:
d
Step-by-step explanation:
cyclic quadrilateral
This statement is always true:
Opposite angles add up to 180°
