Task 4. Fill in the asterisks with six different digits so that all fractions are irreducible and the equation is correct: $\frac{*}{*}+\frac{*}{*}=\frac{*}{*} . \quad[6$ points] (A.V. Lapovalov)
Answer. For example, $\frac{1}{6}+\frac{7}{3}=\frac{5}{2}$ (there are other examples).

Comment. Finding an example is simplified if you notice that no denominator can be equal to 1 (then the denominators of the remaining fractions would coincide), nor 5 or 7 (because if the denominators of two irreducible fractions are not divisible by a prime number, then the denominator of their sum or difference is also not divisible by this prime number).