Mathematics for IGCSE & O level - Ratio And Proportion (Section 4 - No. 16)
A mixture is made using sand and cement in the ratio 2:5. If 10kg of sand is used, how much cement is used?
4 kg
20 kg
25 kg
50 kg
คำอธิบาย
If 2 parts sand = 10kg, then 1 part is 5kg. Cement = 5 parts. so 5*5=25