Andre and Betty together weigh 150 pounds. Betty and Chris together 180…

Let A, B, C, and D represent the weights of Andre, Betty, Chris, and David respectively.

We are given the total weight of all four people is 450 pounds (A + B + C + D = 450).

We know Andre and Betty weigh 150 pounds together (A + B = 150). Subtracting this from the total gives Chris and David's combined weight: C + D = 450 - 150 = 300 pounds.

We are also told Andre, Chris, and David weigh 360 pounds (A + C + D = 360). Substituting the value of (C + D) found above, we get A + 300 = 360, which means Andre weighs 60 pounds.

Since Andre and Betty weigh 150 pounds, Betty weighs 150 - 60 = 90 pounds.

Since Betty and Chris weigh 180 pounds, Chris weighs 180 - 90 = 90 pounds.

Finally, since Chris and David weigh 300 pounds together, David weighs 300 - 90 = 210 pounds.