How much water should be added to 90ml of 45 percent acid solution to dilute it to 25 percent acid solution

72 ml

Step-by-step explanation:

Let

x = amount of water that should be added

45% acid solution = 45/100 = 0.45

25% acid solution = 25/100 = 0.25

The equation is

90(0.45) = 0.25(x + 90)

40.5 = 0.25x + 22.5

40.5 - 22.5 = 0.25x

18 = 0.25x

Divide both sides by 0.25

x = 18/0.25

= 72

x = 72 ml

the answer is 510

step-by-step explanation:

15 • 13 = 195

15 • 12 = 180

15 • 5 = 75

12 • 5 = 60

195 + 180 = 375

375 + 75 = 450

450 + 60 = 510