Suppose 2kg of sugar contains 9*10 crystals.

How many sugar crystals are there in 5 kg of sugar?2) 1.2kg of sugar

225

Step-by-step explanation:

9*10 = 9 times 10 = 90

2kg = 90

that means 1kg = half of 90 = 45

1kg = 45

5 kg = 45 times 5 = 225

By the way at the end of your question you put "2) 1.2kg of sugar" but I don't know what that is so i ignored it