Sure, let's solve the expression step-by-step:
[tex]\[ 2.5 - [6.50 - \{2.80 \div 2 \times (7.5 - 5.4 - 3.9)\}] \][/tex]
1. Innermost parentheses calculation
[tex]\[
7.5 - 5.4 - 3.9
\][/tex]
Compute [tex]\(7.5 - 5.4\)[/tex]:
[tex]\[
7.5 - 5.4 = 2.1
\][/tex]
Now subtract [tex]\(3.9\)[/tex] from [tex]\(2.1\)[/tex]:
[tex]\[
2.1 - 3.9 = -1.8
\][/tex]
2. Division inside the braces
[tex]\[
2.80 \div 2
\][/tex]
Compute:
[tex]\[
2.80 \div 2 = 1.4
\][/tex]
3. Multiplication inside the braces
[tex]\[
1.4 \times (-1.8)
\][/tex]
Compute:
[tex]\[
1.4 \times -1.8 = -2.52
\][/tex]
4. Braces calculation
[tex]\[
6.50 - (-2.52)
\][/tex]
Since subtracting a negative is the same as adding the absolute value:
[tex]\[
6.50 + 2.52 = 9.02
\][/tex]
5. Brackets calculation
[tex]\[
2.5 - 9.02
\][/tex]
Compute:
[tex]\[
2.5 - 9.02 = -6.52
\][/tex]
So, the result of the expression is [tex]\(-6.52\)[/tex].