Let the total number of matches played by the team be x.
It is given that the team won 10 matches and the winning percentage of the team was 40%.
Therefore,
\\(\\begin{array}{l}{\\frac{40}{100} \ imes x=10} \\\\ {x=10 \ imes \\frac{100}{40}} \\\\ {x=25}\\end{array}\\)
Thus, the team played 25 matches.