To evaluate the expression \(4_2 + (3 \times 6) - 7\), we need to follow the order of operations, which is parentheses, exponentiation (which we'll denote as \(x_2\) in your notation), multiplication and division (from left to right), and then addition and subtraction (from left to right).
However, it appears there is no exponentiation in this expression, so we can simplify:
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Evaluate the expression inside the parentheses: \[ 3 \times 6 = 18 \]
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Replace the expression in the parentheses: \[ 4_2 + 18 - 7 \]
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Now we need to evaluate \(4_2\). It seems you are using a subscript to denote base 2. The number \(4_2\) in base 2 is evaluated as follows:
- In base 2, the place values are powers of 2, so: \[ 4_2 = 1 \times 2^2 + 0 \times 2^1 + 0 \times 2^0 = 4 \]
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Now substitute \(4_2\) with 4 in the equation: \[ 4 + 18 - 7 \]
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Perform the addition and subtraction from left to right:
- First, add: \[ 4 + 18 = 22 \]
- Then, subtract: \[ 22 - 7 = 15 \]
So, the final result is: \[ \boxed{15} \]