The best estimate for 1,374 is 1,400 and the best estimate for 6 is 10. This is because anything that is 5 and above you change it. Example: 16 the best estimate for 16 is 20 because 6 is above 5. And when a number is 4 and below you change the number below. Example: 12 the best estimate for 12 is 10 because 2 is below 4. And when the number is perfect like 10, you can keep the number the same. Example:10,20,30,40,50,60etc.
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