Solve : `0.5y + 0.75y = 125`

Answer

To solve the equation \(0.5y + 0.75y = 125\), we will follow these steps:

### Step 1: Combine like terms
First, we combine the terms on the left side of the equation. We have \(0.5y\) and \(0.75y\).

\[ 0.5y + 0.75y = (0.5 + 0.75)y = 1.25y \]

### Step 2: Rewrite the equation
Now, we can rewrite the equation with the combined terms:

\[ 1.25y = 125 \]

### Step 3: Isolate \(y\)
Next, we want to isolate \(y\) by dividing both sides of the equation by \(1.25\):

\[ y = \frac{125}{1.25} \]

### Step 4: Perform the division
To simplify \(\frac{125}{1.25}\), we can multiply both the numerator and the denominator by 100 to eliminate the decimal:

\[ y = \frac{125 \times 100}{1.25 \times 100} = \frac{12500}{125} = 100 \]

### Final Answer
Thus, the value of \(y\) is:

\[ y = 100 \]

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