How do I solve this math word problem?

Question

Four friends hosted a party. Barb paid $11 for drinks, Bonnie paid $15 for food, Pam paid $6 for invitations, and Holly paid $8 for decorations. The friends want to share the party expenses equally, and pam will pay the entire amount she owes to one person. Who owes money to whom?

Answer 1

Pam will pay $4 to Bonnie; Holly will pay $1 to Barb and $1 to Bonnie.

To determine the total amount of money spent on the party, add the money spent by each person together:

$11 + $15 + $6 + $8 = $40

To find how much each person owes, divide the total amount spent by 4:

$40 / 4 = $10

Then, subtract the amount each person paid from $10:

Barb: $10 - $11 = -$1 therefore, Barb is owed $1

Bonnie: $10 - $15 = -$5 therefore, Bonnie is owed $5

Pam: $10 - $6 = $4 therefore, Pam owes $4

Holly: $10 - $8 = $2 therefore, Holly owes $2

Because we know that Pam is paying their entire amount owed to one person, we know that Pam has to be paying Bonnie; Bonnie and Barb are both owed money, but Barb is only owed $1, so it doesn't make sense for Pam to pay Barb.

After Pam pays Bonnie, Bonnie is still owed $1

-$5 + $4 = -$1

Holly still owes $2, and Barb and Bonnie are each owed $1.

Because $1 + $1 = $2, Holly owes Barb and Bonnie $1 each.

In summary:

Pam owes Bonnie $4

Holly owes Bonnie $1

Holly owes Barb $1