Weight Relationships Analysis

Let the weights of the four friends be denoted by A, B, C, and D.

The problem provides the following relationships:

• A is twice as heavy as B: $A = 2B$
• C is half of B's weight: $C = 0.5B$
• D is 60 kg more than B: $D = B + 60$
• D is 60 kg less than A: $D = A - 60$

Calculating Individual Weights

We can use the two equations involving D to find a relationship between A and B:

Since $D = B + 60$ and $D = A - 60$, we can set them equal:

$B + 60 = A - 60$

Rearranging this equation to solve for A:

$A = B + 60 + 60$

$A = B + 120$

Now we have two expressions for A: $A = 2B$ and $A = B + 120$.

Equating these two expressions:

$2B = B + 120$

Subtract B from both sides to find B's weight:

$2B - B = 120$

$B = 120$ kg

Now, calculate the weights of the other friends:

• A's weight: $A = 2B = 2 \times 120 = 240$ kg
• C's weight: $C = 0.5B = 0.5 \times 120 = 60$ kg
• D's weight: $D = B + 60 = 120 + 60 = 180$ kg

Identifying the Heaviest Friend

Compare the calculated weights:

• A = 240 kg
• B = 120 kg
• C = 60 kg
• D = 180 kg

Friend A has the highest weight.