Brackets signify the order of operations in math equations. The order of operations is key to ensuring problems are solved correctly. Improperly handling this order causes errors. The general rule regarding the order of operation is to start with the innermost brackets, work through the middlemost brackets and out to the outermost brackets. In each case, you read from left to right within the bracket and do multiplications, divisions and exponentials first followed by additions and subtractions.
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Solve the math problem in the innermost bracket or parenthesis. Reading from left to right within the innermost bracket, solve multiplications, divisions and exponentials first followed by the additions and subtractions. Take the math problem example {[3(15 + 5) + 27]/3}. In this equation, the innermost bracket is the (15 + 5), which results in reducing the equation to {[3(20) + 27]/3}.

Solve the math problem in the middlemost bracket. Continuing with our example, {[3(20) + 27]/3}, the middle most bracket is [3 (20) + 27]. Working from left to right, [3 (20) + 27] = [3 x 20 + 27] = [60 + 27] = [87]. This reduces the final equation to {[87]/3}. Or, because 87 is by itself in the middlemost bracket, we can eliminate the bracket yielding {87/3}.

Solve the math problem in the outermost bracket. Continuing with our example, {87/3}, the final answer is 29.
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