Saturday, January 4, 2003
M I N D  G A M E S


Carry on calculating
Aditya Rishi

This is the count of 11 (on the middle bar)
This is the count of 11 (on the middle bar).

CALCULATOR to computer (about abacus Abu): "One 1-bead in the 10’s column with one 1-bead in the 1’s column denotes 11 on the middle bar or the abacus’ beam. When the count reaches 15, reset bottom deck and carry one 5-bead over to the upper deck. 

The count reaches 15
The count reaches 15.

When the count reaches 20 (with one 5-bead in the upper deck and five 1-beads in the lower deck), carry one more 5-bead over to the upper deck and reset lower deck. Then, carry one 1-bead over to the column on the left and reset upper deck."

 

This is 15, after the final resetting of decks
This is 15, after the final resetting of decks.

"Counting 5 1-beads on the lower deck requires a carry of one 5-bead to the upper deck. Counting 2 beads on the upper deck requires a carry of 1 1-bead on the lower deck of the column on the left.

The count reaches 20 (first move); second 5-bead also comes down (second move)
The count reaches 20 (first move); second 5-bead also comes down (second move).

Every bead in the lower deck stands for 1 and every bead in the upper deck has value 5. Every column to the left of one’s column is an order of magnitude greater."

Lower deck brought down (third move), upper deck moved back (fourth move) and 1 carried over to the 10’s column (fifth move); this is 20
Lower deck brought down (third move), upper deck moved back (fourth move) and 1 carried over to the 10’s column (fifth move); this is 20.

(to be continued; write at The Tribune or adityarishi99@yahoo.co.in)