Linear equations and inequalities

Solve the following inequality assuming positive integer $x$. $$1\frac{1}{3}\le -\frac{x-4}{2}$$

Find the set of all the positive integers $x$ for which the expression $\frac{3x-7}{14}$ is smaller than $\frac{7-2x}{7}$.

Consider a coil composed from a ferrite core and a wire winding. The mass of the core is $2\mathrm{kg}$. The material for the wire is such that the mass of the wire of the length $30\mathrm{m}$ is bigger than the mass of the wire of the length $10\mathrm{m}$ together with the ferrite core. In the following list identify a possible mass of one meter of the wire.

Solve the following inequality: $$(5+2x)\cdot (-3)+16<20-6x$$