Simplify: `53.5-34.68 +64.75 -28.9`

Answer

To simplify the expression \( 53.5 - 34.68 + 64.75 - 28.9 \), we will follow these steps:

### Step 1: Group the terms
We can rearrange the expression to group the addition and subtraction:
\[ (53.5 + 64.75) - (34.68 + 28.9) \]

### Step 2: Calculate the sum of the first group
Now, we will calculate \( 53.5 + 64.75 \):
\[ 53.5 + 64.75 = 118.25 \]

### Step 3: Calculate the sum of the second group
Next, we will calculate \( 34.68 + 28.9 \):
\[ 34.68 + 28.9 = 63.58 \]

### Step 4: Subtract the second sum from the first sum
Now, we will subtract the result of the second group from the first group:
\[ 118.25 - 63.58 \]

### Step 5: Perform the subtraction
Now, we perform the subtraction:
\[ 118.25 - 63.58 = 54.67 \]

### Final Answer
Thus, the simplified result of the expression \( 53.5 - 34.68 + 64.75 - 28.9 \) is:
\[ \boxed{54.67} \]