Question

2129 divided by 7.2 round to the nearest whole #. Show your work step by step including the long division. Trying to remember this to teach my daughter thank you

Answer 1

Answer:

296

Step-by-step explanation:

There are many ways that long division is taught. Many of us tend to teach it the way we learned it.

In the attachment, we start by adjusting the decimal point one place to the right, so we are dividing the integer 21290 by the integer 72. Down the left side of the page we have listed the multiples of 72 (not a step I learned, but it does make the division easier).

We compare the dividend to the divisor, finding the leftmost set of digits that is greater than or equal to the divisor. 2 is not; 21 is not; 212 is. Consulting our table of multiples, we find that the 212 is between 2×72 and 3×72, so our first quotient digit is 2 (the smaller of these multipliers). We align that quotient digit over the  units digit of 212.

Now, we subtract 2×72 from 212 to get 68, then bring down the next digit from the original dividend. The new problem we have is 689 divided by 72. Again consulting our table of multiples, we find the next quotient digit to be 9. This quotient digit is aligned over the 9 that we brought down from the original dividend.

Repeating the subtraction and bring-down, the new problem is 410 divided by 72. That results in a quotient digit of 5, aligned over the 0 of the original dividend.

After the subtraction, we find we have a remainder of 50. If we wanted the decimal part of the quotient, we would add zeros to the right of the decimal point in the original dividend, and continue on, bringing down zeros as needed to continue the division.

Here, we want to round to the nearest integer, so we only need to know if this remainder is half or more of 72, or less than half of 72. We know half of 72 is 36, so 50 is more than half, and we need to round our quotient up to 296.