Writing to explain: The digit 5 is usually rounded up, but it can also be rounded down. How would you round the numbers in the equation 9.5 +4.7+3.2+7.5= to the nearest whole number without getting an overestimate or an underestimate?
Since all but one of those numbers rounds up, I'd round 7.5 down to 7.
To round the numbers in the equation 9.5 + 4.7 + 3.2 + 7.5 to the nearest whole number without getting an overestimate or an underestimate, we need to use a rounding rule that is consistent and fair.
The general rule for rounding numbers is as follows:
1. If the decimal part of the number is less than 0.5, the number is rounded down (i.e., the integer part is kept as is).
2. If the decimal part of the number is equal to or greater than 0.5, the number is rounded up (i.e., the integer part is increased by one).
Now, let's apply this rule to each number in the equation:
1. For 9.5, the decimal part is exactly 0.5, which means it falls right in the middle. According to the rule, when a number falls precisely in the middle, we need to look at the integer part to determine how to round it. In this case, the integer part is 9, so there is no need to round up or down. Therefore, 9.5 remains as 9.
2. For 4.7, the decimal part is less than 0.5 (0.7), so we need to round it down. The integer part is 4, so the rounded value is 4.
3. For 3.2, the decimal part is less than 0.5 (0.2), so we need to round it down. The integer part is 3, so the rounded value is 3.
4. For 7.5, the decimal part is exactly 0.5, and the integer part is 7. As discussed earlier, we look at the integer part to determine the rounding. Since the integer part is 7, we don't need to round up or down. Therefore, 7.5 remains as 7.
Now, let's substitute the rounded values back into the equation:
9 + 4 + 3 + 7 = 23
Therefore, the rounded value of 9.5 + 4.7 + 3.2 + 7.5 to the nearest whole number without an overestimate or an underestimate is 23.