Exploring Multiplication

[Pasyanthi]

Multiplication is a wonderful way to explore mathematics as well as develop mental powers of agility, memory, flexibility and creativity.

Here are seven methods covered in the course:

1. Base method  e.g. 87×97, Lesson 14,15 (and 31×33 using Proportionately)
   2.         Average  e.g. 41×39, Lesson 17 (and 82×39 using Proportionately)
   3.         By One More  e.g. 74×76, Lesson 17 (and 47×86 using Proportionately)
   4.         Doubling & Halving  e.g. 35×46, Lesson 7
   5.         Eleven  e.g. 43×11 (and 52×22 using Proportionately), Lesson 12
   6.         Addition & subtraction  e.g. 34×19, Lesson 2
   7.         General method (vertically and crosswise)  e.g. 23×31, Lesson 13

(Lesson 32 shows another multiplication method)

You can use addition and subtraction with the other methods too. For example, for 23×42 you could think of this as 22×42 + 42, so that you can use the 11 method to find 22×42 and add 42 to it.

Try these:

62 x 58 =                     42 x 43 =                      11 x 56 =
65 x 85 =                     41 x 38 =                      38 x 39 =
71 x 79 =                     72 x 45 =                      87 x 11 =
31 x 21 =                     78 x 36 =                      21 x 53 =

Can you give a pair of numbers whose product cannot be found by any of the first 6 methods above?
Can you find a pair of numbers whose product can be found using all of the methods above?

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