math homework question.............?

Question

7 dg. 9 cg.
+ 7 cg.




can you please explain to me how you found the answer to because i tried doing it and each time it came out wrong :) thanks

Answer 1

If by dg you mean decigrams and cg you mean centigrams, then
each dg is equal to 10 cg, and each cg is equal to 0.1 cg.

So

7 dg 9 cg

Is the same as

7.9 dg

or

79 cg

So you can do your problem as:

7.9 dg + 0.7 dg = 8.6 dg

Or:

79 cg + 7 cg = 86 cg

So your answer would be 8.6 dg, 86 cg, or 8 dg 6 cg. Your choice.