What is the reading shown on the scale of the vernier calipers, given the main scale reads 3.0 cm and the vernier scale's 8th division aligns with a main scale division?

The zero mark on the vernier scale is past the $3.0 \text{ cm}$ mark on the main scale but has not reached the $3.1 \text{ cm}$ mark.
The main scale reading is $3.0 \text{ cm}$.

Identify the mark on the vernier scale that aligns perfectly with any mark on the main scale.
The 8th mark on the vernier scale aligns with a mark on the main scale.
Each division on the vernier scale represents $0.01 \text{ cm}$.
The vernier scale reading is $8 \times 0.01 \text{ cm} = 0.08 \text{ cm}$.

Total reading = Main scale reading + Vernier scale reading

The reading shown on the scale of the vernier calipers is $\text{3.08 cm}$.