This is the 467th most frequent Russian word.
сумму
The Russian word "сумму" is the accusative form of "сумма," which means "sum" or "total" in English.
In this sentence, 'сумму' refers to the total amount or aggregate of the expenses.
Я добавил сумму всех расходов за месяц.
I added up the total of all expenses for the month.
Here, 'сумму' denotes an unspecified amount of money being offered.
Они предложили сумму, которая меня устроила.
They offered an amount that satisfied me.
'Сумму' in this sentence represents the result of adding numbers together.