Awater tank holds 256 gallons but is leaking at the rate of 3 gallons per week. a second water tank holds 384 gallons and is leaking at a rate of 5 gallons per week. after how many weeks will the amount of water in the two tanks be the same.

Simple

you have: one is leaking 3 gallons per week and holds 256 gallons; whereas, the other one is leaking 5 gallons per week and holds 384 gallons.

Set up both the equations

In y=mx+b form--->>>

y=-3x+256

y=-5x+384

To figure out when they will be equal..set the equations equal to each other(remember to isolate the variable)

-3x+256=-5x+384

-3x+256=-5x+384
      -256        -256

-3x=-5x+128

-3x=-5x+128
+5x+5x

2x=128

x=64

After 64 weeks the amount of water in both tanks will be the same.

Thus, your answer.

The density of the cube is 40

20 percentage, you can also do it on a calculator.