To Find :
How many gallons of a 80% antifreeze solution must be mixed with 100 gallons of 20% antifreeze to get a mixture that is 70% antifreeze.
Solution :
Let, x gallons of 80% antifreeze solution is required :
So,

Therefore, 500 gallons of 80% antifreeze solution is required.
Answer:
x = 10 or x = 2
Step-by-step explanation:
Solve for x:
x^2 - 12 x + 20 = 0
Hint: | Solve the quadratic equation by completing the square.
Subtract 20 from both sides:
x^2 - 12 x = -20
Hint: | Take one half of the coefficient of x and square it, then add it to both sides.
Add 36 to both sides:
x^2 - 12 x + 36 = 16
Hint: | Factor the left hand side.
Write the left hand side as a square:
(x - 6)^2 = 16
Hint: | Eliminate the exponent on the left hand side.
Take the square root of both sides:
x - 6 = 4 or x - 6 = -4
Hint: | Look at the first equation: Solve for x.
Add 6 to both sides:
x = 10 or x - 6 = -4
Hint: | Look at the second equation: Solve for x.
Add 6 to both sides:
Answer: x = 10 or x = 2
Answer:
D. 4/(2/5)
Step-by-step explanation:
For example, if the wood was 8ft long, and was cut into 4 foot long segments, you would divide 8 by 4 to get 2, which is the logical answer. Use the same thinking here. In other words, divide the large piece into smaller pieces.
For this one, divide 4 (large) by 2/5 (small).
If simplification is needed you can make 10 pieces.
Answer:
126/1=126
Step-by-step explanation:
630:5 as a fraction would be 630/5.
630/5 simplified would be 126/1.
Hope this helps :)