7,2:2,4=0,9:@

To solve the expression \( 7,2:2,4=0,9:@ \), we need to first interpret it properly using division and ratios.

In many countries, the comma is used as a decimal separator, so we can interpret the numbers as follows:

• \( 7,2 \) is \( 7.2 \)
• \( 2,4 \) is \( 2.4 \)
• \( 0,9 \) is \( 0.9 \)

Now, let's parse the equation:

1. \( 7.2 : 2.4 \) is equivalent to \( \frac{7.2}{2.4} \).
2. Dividing \( 7.2 \) by \( 2.4 \) gives: \[ \frac{7.2}{2.4} = 3 \]

Now the equation becomes: \[ 3 = 0.9 : @ \]

Next, we can interpret \( 0.9 : @ \) as \( \frac{0.9}{@} \). Setting this equal to 3 results in: \[ \frac{0.9}{@} = 3 \]

Now we can solve for \( @ \): \[ 0.9 = 3 \cdot @ \] \[ @ = \frac{0.9}{3} = 0.3 \]

Thus, the value of \( @ \) is \( 0.3 \).