Answer
$-1\frac{7}{8}$
Work Step by Step
The error is that the reciprocal of the dividend instead of the reciprocal of the divisor was used.
$-\frac{3}{4}\div\frac{2}{5}\longrightarrow$ multiply by the reciprocal of the divisor
=$-\frac{3}{4}\times\frac{5}{2}\longrightarrow$ multiply
=-$\frac{15}{8}\longrightarrow$ reduce
=-$1\frac{7}{8}$
