A block takes $$t$$ time to slide down a plane inclined at 45° to the horizontal. If the surface is made smooth (frictionless), the block takes time $$\dfrac{t}{2}$$ to slide down the plane. The coefficient of friction between the block and the inclined plane is $$\left(\dfrac{\alpha}{100}\right)$$. The value of $$\alpha$$ is __________.