You only have 20% alcohol solution and 50% alcohol solution. How much of each would you need to complete request?
the chemist is asking for 12 liter of 40% alcohol solution. You only have 20% alcohol solution and 50% alcohol solution. How much of each would you need to complete request?
the chemist is asking for 12 liter of 40% alcohol solution. You only have 20% alcohol solution and 50% alcohol solution. How much of each would you need to complete request?
Let x be the amount of 20% alcohol solution
Let y be the amount of 50% alcohol solution
Then 0.2 x + 0.5 y = 12 liter (0.4) = 4.8 liter
also x + y = 12 liter
solve 2 equations 2 unknowns for x and y
0.2 x + 0.5 y = 4.8 ... eq 1
x + y = 12 ... eq 2 Multiply eq 2 by -0.2
0.2 x + 0.5 y = 4.8 ... eq 1
-0.2(x + y = 12) ... eq2
-0.2(x + y = 12) ... eq2
0.2 x + 0.5 y = 4.8...eq1
-0.2 x -0.2 y = -2.4...eq2 Add equations
0.3y = 2.4 , y = 2.4/0.3 = 8 substitute y=8 in eq1
x+8=12. x=12-8, x = 4
you need 4 liters of the 20% alcohol and 8 liter of 50% alcohol
Check 0.2 x + 0.5 y = 0.2(4)+0.5(8)=0.8+4=4.8 checks
