What is obtained when we subtract 21 kg 370 g from 37 kg 675 g without conversion into gram.
${\text{A}}{\text{.}}$ 15 kg 305 g
${\text{B}}{\text{.}}$ 15 kg 470 g
${\text{C}}{\text{.}}$ 16 kg 305 g
${\text{D}}{\text{.}}$ 16 kg 300 g

Hint- Here, we will proceed by using the concept that any quantity which is given as a kilogram b gram can be represented as a kilogram + b gram. Then, we will subtract the corresponding kilogram terms and gram terms individually.

Complete step-by-step solution -
Let us suppose that the given two quantities are represented as A = 21 kg 370 g and B = 37 kg 675 g where kg represents kilogram unit and g represents gram unit.
In the problem, it is asked not to convert the units of these quantities into grams.
Since, A = 21 kg + 370 g$ \to (1)$
and B = 37 kg + 675 g$ \to (2)$
Subtracting equation (1) from equation (2), we get
B-A = (37 kg +675 g) – (21 kg + 370 g)
$ \Rightarrow $B-A = 37 kg +675 g – 21 kg - 370 g
$ \Rightarrow $B-A = (37 kg - 21 kg) + (675 g - 370 g)
$ \Rightarrow $B-A = 16 kg + 305 g
$ \Rightarrow $B-A = 16 kg 305 g
Therefore, when we will subtract 21 kg 370 g from 37 kg 675 g we will get 16 kg 305 g
Hence, option C is correct.

Note- In this particular problem, if we were asked to find the quantity obtained when we subtract 21 kg 370 g from 37 kg 675 g with conversion into gram. In that case, we would have used the formula 1 kg = 1000 g which would have given A = 21 kg 370 g = 21,370 g and B = 37 kg + 675 g = 37,675 g. Then, B-A = 37675 – 21370 = 16,305 g = 16 kg + 305 g = 16 kg 305 g.