Simplify the following:

[tex]\[
\begin{array}{l}
4 + 6 - 7 \times 15 \div 3 \\
44 - \{26 + (-84 \times 84 \div 42)\} \\
230 \times [184 - \{276 \div 138 \times 124 \div 4 - 30\}]
\end{array}
\][/tex]

Use the order of operations to simplify.



Answer :

Let's simplify the given expressions step-by-step using the order of operations (PEMDAS/BODMAS).

### Expression 1: [tex]\( 4 + 6 - 7 \times 15 \div 3 \)[/tex]

1. Multiplication and Division (left to right):
[tex]\[ 7 \times 15 = 105 \][/tex]
[tex]\[ 105 \div 3 = 35 \][/tex]

2. Addition and Subtraction (left to right):
[tex]\[ 4 + 6 = 10 \][/tex]
[tex]\[ 10 - 35 = -25 \][/tex]

So, the simplified result of the first expression is:
[tex]\[ 4 + 6 - 7 \times 15 \div 3 = -25.0 \][/tex]

### Expression 2: [tex]\( 44 - \{26 + (-84 \times 84 \div 42)\} \)[/tex]

1. Calculate inside the curly brackets:

a. Multiplication and Division (left to right):
[tex]\[ -84 \times 84 = -7056 \][/tex]
[tex]\[ -7056 \div 42 = -168 \][/tex]

b. Addition inside the braces:
[tex]\[ 26 + (-168) = -142 \][/tex]

2. Subtraction outside the braces:
[tex]\[ 44 - (-142) = 44 + 142 = 186 \][/tex]

So, the simplified result of the second expression is:
[tex]\[ 44 - \{26 + (-84 \times 84 \div 42)\} = 186.0 \][/tex]

### Expression 3: [tex]\( 230 \times [184 - \{276 \div 138 \times 124 \div 4 - 30\}] \)[/tex]

1. Calculate inside the curly brackets:

a. Division and Multiplication (left to right):
[tex]\[ 276 \div 138 = 2 \][/tex]
[tex]\[ 2 \times 124 = 248 \][/tex]
[tex]\[ 248 \div 4 = 62 \][/tex]

b. Subtraction inside the braces:
[tex]\[ 62 - 30 = 32 \][/tex]

2. Subtraction inside the square brackets:
[tex]\[ 184 - 32 = 152 \][/tex]

3. Finally, multiplication:
[tex]\[ 230 \times 152 = 34960 \][/tex]

So, the simplified result of the third expression is:
[tex]\[ 230 \times [184 - \{276 \div 138 \times 124 \div 4 - 30\}] = 34960.0 \][/tex]

### Summary

The simplified results for the given expressions are:
1. [tex]\( 4 + 6 - 7 \times 15 \div 3 = -25.0 \)[/tex]
2. [tex]\( 44 - \{26 + (-84 \times 84 \div 42)\} = 186.0 \)[/tex]
3. [tex]\( 230 \times [184 - \{276 \div 138 \times 124 \div 4 - 30\}] = 34960.0 \)[/tex]