New coder Javascript issue

the question I was asked was, ” You order one coffee ($5.99) and one bagel ($2.99). Using math , calculate the total cost and using concatenation , create the text : ‘ Total cost:$_’.”
the code I answered with was ‘Total cost : $${( 599 + 295 ) / 100}’ and it doesn’t seem to be the solution . I would love to know a solution to the question please