Simplify:

Question

5.5 plus 7 left square bracket left-parenthesis 6.3 plus 2.1 right-parenthesis times 4 plus left-parenthesis 10 minus 4 right-parenthesis divided by 2 right square bracket

Answer options with 5 options
A.
144.1

B.
164.7

C.
243.7

D.
261.7

E.
296.7

Answer 1

Let's simplify the expression step by step:

The given expression is: \[ 5.5 + 7 \left[ (6.3 + 2.1) \times 4 + (10 - 4) \div 2 \right] \]

1. Calculate the expressions in the parentheses:

   • For \(6.3 + 2.1\): \[ 6.3 + 2.1 = 8.4 \]

   • For \(10 - 4\): \[ 10 - 4 = 6 \]

2. Now substitute back into the expression: \[ 5.5 + 7 \left[ (8.4) \times 4 + (6) \div 2 \right] \]

3. Calculate \( (8.4) \times 4 \): \[ 8.4 \times 4 = 33.6 \]

4. Calculate \( 6 \div 2 \): \[ 6 \div 2 = 3 \]

5. Combine the results in the brackets: \[ 33.6 + 3 = 36.6 \]

6. Now, substitute that back into the expression: \[ 5.5 + 7 \left[ 36.6 \right] \]

7. Calculate \( 7 \times 36.6 \): \[ 7 \times 36.6 = 256.2 \]

8. Finally, add \( 5.5 \) to that result: \[ 5.5 + 256.2 = 261.7 \]

Thus, the simplified expression equals: \[ \boxed{261.7} \]

The correct answer is D. 261.7.