Answer :
The number of gallons that must be needed to antifreeze 50% solution is 105.
Given that 50% antifreeze solution must be mixed with 70 gallons of Strength 25% antifreeze to get a mixture that is 40% antifreeze.
The six-step method involves a few steps that need to perform. These are defining the problem, determining the root cause, finding the alternative solution to solve the problem, selecting the solution, implementing the solution, and finally evaluating the outcome.
Let's consider x be the number of gallons of a 50% antifreeze solution.
As we know we need to make an antifreeze solution by adding the given quantities.
Hence,
x×50%+70×25%=40%×(x+70)
x×0.5+70×0.25=0.4×(x+70)
Now, we will multiply the numbers, we get
0.5x+17.5=0.4(x+70)
Now, we will multiply both sides by 10, we get
0.5x×10+17.5×10=0.4(x+70)×10
5x+175=4(x+70)
5x+175=4x+280
Further, we will subtract 175 from both sides, we get
5x+175-175=4x+280-175
5x=4x+105
Furthermore we will subtract 4x from both sides, we get
5x-4x=4x+105-4x
x=105
Hence, 105 gallons of 50% antifreeze solution must be needed.
Learn more about antifreeze solution from here brainly.com/question/20700320
#SPJ9
