`a:b=0*66`, Find `a:b=?`

Answer

To solve the problem where \( a:b = 0.66 \), we will follow these steps:

### Step 1: Understand the Ratio
We know that the ratio \( a:b \) can be expressed as a fraction:
\[ \frac{a}{b} = 0.66 \]

### Step 2: Convert Decimal to Fraction
To convert the decimal \( 0.66 \) to a fraction, we can express it as:
\[ \frac{a}{b} = \frac{66}{100} \]

### Step 3: Simplify the Fraction
Next, we simplify the fraction \( \frac{66}{100} \). We can divide both the numerator and the denominator by their greatest common divisor (GCD). The GCD of 66 and 100 is 2:
\[ \frac{66 \div 2}{100 \div 2} = \frac{33}{50} \]

### Step 4: Write the Ratio
Now that we have simplified the fraction, we can express the ratio \( a:b \):
\[ a:b = 33:50 \]

### Final Answer
Thus, the ratio \( a:b \) is:
\[ \boxed{33:50} \]

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