The standard algorithm is a quick way to solve multiplication calculations. Which student has correctly started the standard algorithm for this calculation: 26 times 49?
Before we solve this question, let’s remind ourselves what it means by standard algorithm. An algorithm is just a process or set of rules that we follow in calculations. All four of these multiplication problems are set up using the standard algorithm. What we wanna do is set up our own multiplication problem and then compare it to these four students.
How do we multiply 26 by 49? The most important thing is to line them up vertically, making sure that their units are in line. So the ones place, here, the six and the nine line up. Also, the digits in the tens place line up. Here are the two and the four.
When they’re lined up vertically, then you’re ready to multiply. What we want to do now is see which of these four options looks like the problem that we’ve set up.
Student a has added a zero in the units place that should not be there. Student b is missing the nine from the 49. And he’s lined up the units incorrectly. Student c has put the tens place in the wrong place, leaving us with student d who has correctly lined up and started the standard algorithm for this calculation.