The temperature in a city on Thursday is ^@19^\circ C^@. If the temperature falls by ^@9^\circ C^@ on Friday and increases by ^@3^\circ C^@ on Saturday. What is the temperature in the city on Saturday?
A factory manufactures cars and motorcycles in the ratio 12:17. If they make 1680 cars in a given period, how many motorcycles do they make in the same period?
Nancy can finish a work in 39 minutes. Richard works twice as fast as Nancy. How long will it take to finish the work, if Nancy and Richard work together?