The multiplicative problems They are taught to children in basic school, after learning the facts of addition and subtraction, also called addition and subtraction..
It is important to teach children that the multiplication of whole numbers is really a sum, but it is essential to learn to multiply to do these additions more quickly and easily.
It is essential to choose well the first problems that will be used to teach children to multiply, as they must be problems that they can understand and can see the usefulness of learning to multiply.
It is not enough to simply teach them the multiplication tables mechanically, it is much more attractive to show them their use through situations that arise in everyday life, such as when their parents go shopping..
There are a large number of problems that can be used to teach a child to apply multiplication tables, below are some problems with their solutions.
A librarian has to sort the books on the library shelves. At the end of Friday afternoon, the librarian realizes that he still needs to order 78 boxes of books, which have 5 books each. How many books will the librarian have to order next week?
Solution: In this problem, it should be noted that all the boxes have the same number of books. Therefore, 1 box represents 5 books, 2 boxes represent 5 + 5 = 10 books, 3 boxes represent 5 + 5 + 5 = 15 books. But doing all these sums is a very extensive process.
Carrying out all the above sums is equivalent to multiplying the number of books in each box by the number of boxes remaining to order. Namely, 5 × 78, therefore the librarian needs to order 390 books.
A farmer needs to pack the coffee obtained in his last harvest in boxes. The total harvest is 20,000 kilos and the boxes in which he is going to pack them have a maximum capacity of 100 kilos. How many boxes does the farmer need to pack the whole harvest?
Solution: The first thing to notice is that all boxes have the same capacity (100 kilos). So if the farmer uses 2 boxes then he can pack only 100 + 100 = 200 kilos. If you use 4 boxes then you will pack 200 + 200 = 400 kilos.
As before, doing all this amount of addition is a very long process. The key is to find a number that when multiplied by 100 the result is 20,000.
Investigating in detail it can be seen that this number is 200, since 200 × 100 = 20,000.
Therefore, the farmer needs 200 boxes to pack the entire harvest..
Maria just moved into a building and would like to know how many windows the building has on the front. The building has 13 floors and on each floor there are 3 windows.
Solution: in this problem you can count the number of windows floor by floor and add them to obtain the answer.
But, since each floor has the same number of windows, it is much faster to multiply the number of floors by the number of windows on each floor. That is, 13 × 3, therefore the building has 39 windows.
Javier is a bricklayer who is building a bathroom floor. So far Javier has placed 9 tiles (squares) on the bathroom floor as shown in the figure below. How many tiles does it take to cover the entire bathroom floor?
Solution- One way to solve this problem is to finish filling in the figure by drawing the missing tiles and then counting them.
But, according to the picture, the bathroom floor can fit 5 tiles horizontally and 4 vertically. Therefore, the entire bathroom floor will have a total of 5 × 4 = 20 tiles.
The months January, March, May, July, August, October and December have 31 days each. What is the total number of days that all these months add up?
Solution: in this exercise, data is explicitly given which is the number of days (31). The second data is given implicitly in the months (7). Therefore, the total days between all these months is 7 × 31 = 217.
Yet No Comments