за три дня продали 1400 кг картофеля, в первый день продали на 100 меньше, чем во второй, а в третий день 3/5 от первого. сколько кг картофеля продали в каждый день

I received that emergency call nearly midnight. A worried male voice informed the emergency service that his three kids 1) … not at home yet. The man explained that his two sons 2) … for a bicycle ride and there was no sign of them yet. I had to ask some questions to understand the details. It turned out that the kids liked to ride down the hills which were four kilometers away from their house. The rescue party headed right there.

The rescuers saw the boys soon. They 3) … the hill. They were walking very slowly. Two of them were helping the third boy – his leg 4) … . Later he told us that they had been practicing extreme cycling.

Unfortunately, things like that happen quite often. People often ignore safety rules, and get injured or worse. They cannot realize that without a very careful preparation any extreme sport is a 5) … activity.

a)

b)

c)

d)

1

are

was

were

had been

2

left

was left

have left

had left

3

move down

are moving down

had moved down

were moving down

4

was broken

has been broken

is broken

broke

5

danger

dangerous

dangerously

endangered

Как решить 0,9 его равны 1 целая 2/7?1 целая 2/7 надо делить на 9/10?Или как?там я помню ещё можно как то по другому,типо 1 целая*100:9/10.Или умножение на 100 это только с процентами???