Mrs. Jewel took a package and 2 letters to the post office in a foreign country where they found the package weighed 1.2 kilograms, the first letter weighed 25 grams and the second letter weighed 42 grams. How much did the three items weight in kilograms altogether?

So,

To find the three items' weight together, we will have to find the sum of the three objects. We must first have them in the same unit.

Conversion factor between kg and g:

1 kg. = 1000 g.

1.2 kg. = 1200 g.

Now add the numbers together.

1200 + 25 + 42 = 1267 g.

Convert back to kg.

1267 g. - - > 1.267 kg.

Altogether, the three items weighed 1.267 kg.