请问这题怎么写？

Question

怎么写？

Answer 1

6 / (2/5)=15
6 / (2/5)

=6X(5/2)
=30/2
=15

Answer 2

6*5/2=6/2*5=3*5=15

Answer 3

6÷（2÷5）
=6÷2×5
=3×5
=15