Answer
2.1 kilograms of potatoes was ate by the guest
Explanation
Total weight of potatos cooked = 7 kilograms
The guest ate 3/10 of the amount cooked
The amount of kilogram ate = 7 x 3/10
The amount ate = 7 x 3 / 10
The amount ate = 21/10
The amount ate = 2.1 kilograms
Therefore, the guest ate 2. 1 kilograms of the potatoes cooked
It will be 21/10 = 2.1
