How do you compute total fixed cost assuming a break even in dollars is nine hundred thousand dollar and variable cost is 630000 income tax is forty percent and contribution margin ratio is thirty per?

A contribution margin of 30% translates to Sales of $900,000 (sales-variable cost)/sales=contribution margin ratio. Since this sales level is also the break even point, there is no operating profit. Thus, a 40% tax rate is immaterial and total fixed cost equals sales minus variable cost or $270,000.