I really enjoyed exploring Problem 13 .
First: Think of 2 digits, only declare the 1st digit .
Next: Place the 2 digits together, and use that number to minus off the sum of the two digits.
Initially i was not able to figure it it out but I eventually manage to figure out the concepts.
The answers can be found out through different ways. the simplest would be to multiply the 1st digit with 9!!
When i was a kid, i was made to memorize the multiplication table.. i remember standing at a corner reading the multiplication aloud to my mum... if you ask me does it helps me with my math? i would say yes somehow it helps me .. but it that the best method..hmm I'm not too sure about that..
Activtty: Multiple sets of 7...
Method 1- doubling certain sets
Eg: 2x7= 14 , so 4x7= 14+ 14 = 28
Method 2- Adding together 2 sets of 7
Eg: 3x7= 21& 6x7= 42,
9x7= 21 + 42 = 63