Final answer:
When rounding to the nearest ten, we look at the digit in the ones place. If this digit is 0-4, the number rounds down to the nearest ten. If the digit is 5-9, the number rounds up to the nearest ten. In the case of 424, the digit in the ones place is 4, so it rounds down. Therefore, 424 rounds to 420 when rounded to the nearest ten
Step-by-step explanation:
When rounding the number 424 to the nearest ten, we apply the rules of rounding. If the digit in the ones place is 5 or more, we round up to the next ten. If it's 4 or less, we round down. Since the digit in the ones place of 424 is a 4, it is less than 5, so we round down. Therefore, 424 rounds to 420 when rounded to the nearest ten.