To enact the SUBTRACTION of 7 - 4

1. Let THE MINUEND KID stand on 7th STEP of STAIRS, and the SUBTRAHEND KID on 4th STEP of STAIRS.

2. They DESCEND IN CADENCE ("in-step") until SUBTRAHEND KID IS AT BOTTOM.

3. Then, POSITION of MINUEND KID COUNTS THE DIFFERENCE of the SUBTRACTION.

This can be written out as a SUCCESSION ON SUBTRACTIONS BY ONE, or COUNTS DOWN:

• 7 - 4 = 6 - 3 = 5 - 2 = 4 - 1 = 3 - 0 = 3.

• Then HOPPY PRINTS 7 - 4 = 3.

HOPPY performs other SUBTRACTIONS similarly.

THIS TRANSFORMS EVERY SUBTRACTION INTO ONE EASY FOR THE STUDENT.

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FLOWCHART FOR HOPPY'S "STAIRCASE SUBTRACTION TRICK"

                       \=======/
                        \START/
                         \   /
                          \_/
                           |
                           V
                   ________|__________
                   |MINUED KID on STEP|
                   |SUBTRAHEND KID on |
                   |SAME LOWER STEP   |
                   --------------------
                           |
                           V
                           |
                          / \                 _______________________
                         /   \->--------Y-----|REPORT ZERO DIFFERENCE|--->---/\
                        / ARE \               -----------------------       /  \                                        / THEY  \              /\                           /    \
                --->--/ on SAME \-->---N-----/IS\                         / STOP \
                ^      \ STEP? /            /SUB-\                        --------
                |       \     /            /TRAHND\                              
                |        \   /            / KID AT \                              
                |         \ /            /  BOTTOM? \
                |          |             -------------
                |          |             /
                |          v            /
                |          |           /
                |          |          /
                |      ____|_________v____
                |     |EACH DESCENDS ONE  |
                -----<|STEP, IN UNISON    |
                      --------------------

EXAMPLE with HOP-SQUARES and FLOWCHARTS [UNDER CONSTRUCTION].

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ANITONIC DIAGRAM FOR HOPPYADDS:

              MAXTONE(UNISON STEPS UP)   MINTONE(STEPS OF MINUEND KID FROM BOTTOM)
      ^                        |
      |                        |
      |                        |
      |                        |
       |                        v