Rounding numbers makes the number more simple (bump it up or down), but keeps it close to the original number. Each number has its own place. A number can be rounded to any place value you want.
When rounding numbers to a certain place, you have to know which number to look at:
10's place = 20 (2 is in the 10's place because there is only one number after it)
100th place = 345 (3 is in the 100th place because there are two numbers after it)
1,000th place = 2345 (2 is in the 1,000th place because there are three numbers after it)
10,000th place = 345678 (3 is in the 10,000th place because there are four numbers after it)
So to answer your question, 265,374,000
Find the ten thousand place, think of 10,000...how many numbers are after the 1? Answer = 4
In your number 264,374,000 find the number that has four numbers after it.... Answer = 7
To begin the rounding, look at the digit one place to the right of the 7, or the 4, which is in the thousands place.
So, 264,374,000 rounded to the ten-thousands place is 264,370,000.
Once you find the correct spot for which number to round, look at the number to the right of it. Answer = 4
Is the number 4 greater than or less than 5? Answer = less than
Since the 4 is less than 5, we'll round our number to zero
Leaving the 7 in the ten-thousands place alone.
The result is: 264,370,000.
0,1,2,3 and 4 round "down" to 0
5,6,7,8 and 9 round up (increase the last digit remaining by 1)