Solution

Multiplicative inverse of a number $$P$$ is $$\dfrac1P$$ as $$P\times\dfrac1P = 1$$

i) Multiplicative inverse of $$-13$$ is $$-\dfrac{1}{13}$$

ii) Multiplicative inverse of $$\dfrac 15$$ is $$5$$

iii) $$\dfrac { -5 }{ 8 } \times \dfrac { -3 }{ 7 } =\dfrac { 15 }{ 56 } $$
Multiplicative inverse = $$\dfrac { 56 }{ 15 } $$

iv) $$\dfrac { -2 }{ 5 } \times -1 = \dfrac { 2 }{ 5 } $$
Multiplicative inverse $$=\dfrac {5 }{ 2 } $$

v) Multiplicative inverse of $$-1$$ is $$-1$$.