5. Round to the nearest hundred. Then find the estimated sum of the two numbers. 465+778W500 + 1,000 = 1,500500-800 = 1,300400-700= 1,100400-800 = 1,200

Given:
We're given two numbers:
465 and 778
To find:
We need to find the nearest 100 of both the numbers, then add both of them.
Step-by-step solution:
First of all, we will calculate the nearest 100 of both of the numbers:
1) 465 = 500
2) 778 = 800
Upon adding both of the numbers:
500 + 800 = 1300
Final answer:
Option B
500 + 800 = 1300