Jeremy has 586 rocks in his rock collection. About how many rocks does Jeremy have, rounded to the nearest ten?
The correct answer and explanation is:
To round 586 to the nearest ten, we focus on the ones digit, which is 6. If the ones digit is 5 or greater, we round up the tens digit. If it is less than 5, we leave the tens digit unchanged.
Here, the ones digit is 6, which is greater than 5. This means we round the tens digit (8) up by 1. Therefore, the tens place becomes 9, and the ones digit becomes 0.
Thus, 586 rounded to the nearest ten is 590.
The process of rounding to the nearest ten involves looking at the number in the ones place and making a decision based on that digit. When the ones digit is 5 or higher, rounding up is the rule. In this case, 586 has a ones digit of 6, so the rounding rule dictates that we increase the tens digit and set the ones digit to 0.
This method is useful in situations where exact values are unnecessary, and we need to simplify or estimate quantities. Rounding can make it easier to handle numbers in everyday situations, such as estimating total costs, counting items in large quantities, or making rough calculations where precision isn’t critical. In this case, rounding Jeremy’s 586 rocks to 590 provides a reasonable estimate of his collection size while keeping the number easy to work with.