Two rigid massless rods PR and RQ are joined at frictionless pin-joint R and are resting on ground at P and Q, respectively. A vertical force F acts on the pin R. When the included angle θ < 90°, the rods remain in static equilibrium due to Coulomb friction between the rods and ground at locations P and Q. At θ = 90°, impending slip occurs simultaneously at points P and Q. Then the ratio of the coefficient of friction at Q to that at P (µQ /µP) is _________ (round off to two decimal places).