Answer:
D. 78.7
Explanation:
To round this to the nearest tenth, first find the digit in the tenths place. This is 6.
Next we look at the digit behind the tenths. If this digit is 5 or more, we round the tenths place up. If the digit behind is 4 or less, we leave the tenths place alone.
The digit behind the tenths place is 8; this means we round the tenths place up. This gives us 78.7.