15/2 :7,5

To solve the expression \( \frac{15}{2} : 7.5 \), we can rewrite the division as a multiplication by the reciprocal:

\[ \frac{15}{2} \div 7.5 = \frac{15}{2} \times \frac{1}{7.5} \]

Now, we can convert 7.5 to a fraction for easier calculation:

\[ 7.5 = \frac{75}{10} = \frac{15}{2} \]

Now we have:

\[ \frac{15}{2} \times \frac{1}{\left(\frac{15}{2}\right)} = \frac{15}{2} \times \frac{2}{15} \]

When we multiply these fractions, the \(15\) in the numerator cancels with the \(15\) in the denominator, and the \(2\) in the numerator cancels with the \(2\) in the denominator:

\[ = 1 \]

Therefore,

\[ \frac{15}{2} : 7.5 = 1 \]