Express the ratio in simplest form :
` 40:20`

Answer

To express the ratio 40:20 in its simplest form, follow these steps:

### Step 1: Write the Ratio
Start by writing the ratio as a fraction:
\[ \frac{40}{20} \]

### Step 2: Simplify the Fraction
To simplify the fraction, divide both the numerator (40) and the denominator (20) by their greatest common divisor (GCD). The GCD of 40 and 20 is 20.

\[ \frac{40 \div 20}{20 \div 20} = \frac{2}{1} \]

### Step 3: Write the Simplified Ratio
Now, express the simplified fraction back as a ratio:
\[ 2:1 \]

### Final Answer
Thus, the simplest form of the ratio 40:20 is:
\[ \text{2:1} \]