Calculate 70.75 plus 78.9.
We can take these two values and line them up vertically. They would look something like this. It’s really important here that we keep the place values lined up. And we can do that by making sure that the decimal points are in line. After everything is lined up correctly, we’re ready to add.
70.75 has a five in the hundredths place. 78.9 doesn’t have anything in the hundredths place. So we say five plus zero equals five. And then, we move on to the tenths place. Seven tenths plus nine tenths equals 16 tenths. We can write that as six tenths and one whole.
After that we bring down our decimal place and then add the ones place. One plus zero plus eight equals nine. Seven plus seven equals 14. The sum is 149.65.
70.75 plus 78.90 equals 149.65.