To solve the problem of estimating the sum of [tex]\( 65.2 + 12.7 \)[/tex] to the nearest whole number, we will follow these steps:
1. Addition:
- Start by adding the two numbers [tex]\( 65.2 \)[/tex] and [tex]\( 12.7 \)[/tex].
[tex]\[
65.2 + 12.7 = 77.9
\][/tex]
2. Rounding to the Nearest Whole Number:
- Next, we need to round [tex]\( 77.9 \)[/tex] to the nearest whole number.
- When rounding, if the decimal part (the part after the decimal point) is less than 0.5, we round down. If it is 0.5 or greater, we round up.
- In this case, the decimal part of [tex]\( 77.9 \)[/tex] is [tex]\( 0.9 \)[/tex], which is greater than 0.5. Therefore, we round up.
[tex]\[
77.9 \approx 78
\][/tex]
So, the estimated sum of [tex]\( 65.2 + 12.7 \)[/tex] to the nearest whole number is:
c) 78
