The easiest way to do it (for me) is to find how many 1 percent represents. So we must divide the net income by 100:
2,376.80 / 100 = 23,768 (that's 1% of the income)
23 * 23,768 = 546,664 (that's 23% of the income)
As we are talking about money, we can round it to $546,66. That's how much money is allotted for food.