5 kgs of cement was mixed with 2 kgs of Sand. If the quantity of sand is tripled and that of cement is doubled, find the new ratio between cement and sand.
5 : 3
2 kgs of sand when tripled gives 2×3 = 6 kgs
5 kgs of cement when doubled gives 5×2 = 10 kgs
∴ Ratio between cement and sand = 10 : 6 or 5 : 3