10000
1000000000
20,000
What is 56 rounded to its greatest place value
The greatest place value will be whatever non-zero digit is farthest to the left. Look at the digit immediately to the right of it. If that digit is four or less, zero it and everything to the right of it out. If that digit is five or higher, increase the greatest digit by one and zero everything to the right of it out.
10000
200,000
It is 1000.
20,000
Round 152+269 to the greatest place value
4000
1000000000
20,000
5000
It is 72.
100
It is 80.