Difference between balance and cost

[Rich7]

Test No. incompl/advan-11 "Finance", question 9

There is still an outstanding ......... on that account, which must be paid in 30 days.

(a) balance
(b) scale
(c) difference
(d) cost

Test No. incompl/advan-11 "Finance", answer 9

There is still an outstanding balance on that account, which must be paid in 30 days.

Correct answer: (a) balance

Your answer was: incorrect
There is still an outstanding cost on that account, which must be paid in 30 days.
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Outstanding balance that must be paid?

[Alan]

Balance here is the sum of money which is the difference between what you have paid and what you still owe.
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