Answer :

Certainly! Let's solve the equation step-by-step.

First, we need to simplify each fraction separately:

1. [tex]\(\frac{1500}{100}\)[/tex]:
[tex]\[ \frac{1500}{100} = 15 \][/tex]

2. [tex]\(\frac{400}{20}\)[/tex]:
[tex]\[ \frac{400}{20} = 20 \][/tex]

3. [tex]\(\frac{50}{50}\)[/tex]:
[tex]\[ \frac{50}{50} = 1 \][/tex]

4. [tex]\(\frac{645}{645}\)[/tex]:
[tex]\[ \frac{645}{645} = 1 \][/tex]

Now that we've simplified the fractions, our expression becomes:
[tex]\[ 15 + 20 + 1 - 1 \][/tex]

Next, let's perform the addition and subtraction in order:

1. First, add the fractions:
[tex]\[ 15 + 20 = 35 \][/tex]

2. Then, add the next term:
[tex]\[ 35 + 1 = 36 \][/tex]

3. Finally, subtract the last term:
[tex]\[ 36 - 1 = 35 \][/tex]

Therefore, the result of the expression [tex]\( \frac{1500}{100} + \frac{400}{20} + \frac{50}{50} - \frac{645}{645} \)[/tex] is [tex]\( 35 \)[/tex].

The answer is:
a) 35