Five lorries were each loaded with 186 bags of cement. How many bags of cement were there in total? Round your answer to the nearest 100.
As there were five lorries and each had 186 bags, we need to multiply 186 by five. One way of doing this would be using column multiplication. Firstly, we would multiply five by six. This gives us 30. We put zero in the units column and carry the three. Next, we need to multiply five by eight, which gives us 40. Adding the three that we carried gives us 43. Three goes in the tens column. And we carry the four. Finally, we need to multiply five by one, which gives us five. Adding the four gives us nine, which we put in the hundreds column. Therefore, 186 multiplied by five is equal to 930.
An alternative method would’ve been to have split the 186 into 100, 80, and six. We could then multiply each of these by five individually. 100 multiplied by five is equal to 500. 80 multiplied by five is equal to 400 as eight multiplied by five is equal to 40. And we add the extra zero. Finally, six multiplied by five is equal to 30. Adding these three numbers also gives us an answer of 930.
We have worked out that there were 930 bags of cement in total. However, we were asked to round our answer to the nearest 100. If we consider the number line between 900 and 1000, then the midpoint is 950. As 930 is less than this, we’ll round down to 900.
This means that, in total, there were 900 bags of cement to the nearest 100.