For this case we have the following solution. x = gallons of water to be added For the 10% solution we have: 0.1 * 8 = 0.8 Then, for 5% we have: (0.8 / x + 8) = 0.05 Rewriting: (0.8 / x + 8) = (5/100) Answer: An equation can be used to find x, the humber of gallons of water he should add is: (0.8 / x + 8) = (5/100)
So first you would make 2 3/7 a dismal. So that is 2.43. Then you add 2.43 and 3.56 to get 5.99 inches tall. The you round to the nearest whole number to get 6 inches.
