Teacher | : | Why is it necessary for students to learn "nnnnn x 10 = nnnnn x 10 for any nnnnn" ? |
You | : | Because it is one of the formula we (implicitely) use in the calculation of, for example, "458 x 7212". Like this : ......
By the way, it is a good exercise for you to pick up all formula which you are, in the logical sense, implicitely using in the calculation of "458 x 7212". |
Teacher | : | Please show me all the formula I, in the logical sense, use in the calculation of "458 x 7212". |
You | : | Ok, look this ..... |