To find the efficiency of the ramp, you can use the formula for efficiency:
\[ \text{Efficiency} = \left( \frac{\text{Useful Work Output}}{\text{Total Energy Input}} \right) \times 100% \]
In this case, the useful work output is 1,200 joules and the total energy input is 2,000 joules. Plugging in the values:
\[ \text{Efficiency} = \left( \frac{1,200 \text{ joules}}{2,000 \text{ joules}} \right) \times 100% \]
Calculating this gives:
\[ \text{Efficiency} = \left( 0.6 \right) \times 100% = 60% \]
Therefore, the efficiency of the ramp is 60%.