hope this helps

kil·o·gram –noun

1. a unit of mass equal to 1000 grams……..

So if a kilogram is 1000 grams and you want to know how many kilograms equals 100 grams what do you have to do to figure this out?

x kilograms = 100 grams

We know that

1 kilogram = 1000 grams

so to find out how many kilograms equals 100 grams, let’s divide each side of our equation by a number that will leave us with 100 grams on one side. What do we need to divide 1000 by to get 100? Let’s try ten. If we divide 1000 by 10 we can figure out the answer by moving the decimal one place to the left (1000. divided by 10 = 100.)

So

1 kilogram divided by 10 = 100 grams

moving the decimal one place to the left for the left side gives us:

.1 kilogram=100 grams (.1 is one-tenth)

RE:
How many kilograms equals 100 grams?

so…

100 grams = .1 kilograms

Therefore, 100 grams = 0.1 kilograms

1000 grams = 1 kilogram

So you need a thousand of them to have one gram.

And you need 100,000 of them to have 100 grams.

Of the choices given, B is the most reasonable. A is equal to about 22 pounds, which is ridiculous. C is a little over one fifth of a pound, which is still too heavy.