Introduce +5 Combination

INTRODUCE COMBINATION

+5 Combination

+4 = +5 – 1

+3 = +5 – 2

+2 = +5 – 3

+1 = +5 – 4

PROBLEM SOLVE

The class was started with a problem, now this is the time to solve the problem. Now its time to solve the problem.

I have 1 and want to add 4, but I can’t add 4 so this is a problem. I have to take the help of our friend 5.

Here 5 will come out to help 4 that is why it can’t help 1, so 4’s close friend 1 will leave. 5 can help only 1 person at a time.

EXAMPLE (FINGERS)

1 + 4 + 4

Step 1 To add 1, open index finger of unit hand

Step 2 To add 4, need to open Thumb (5) and close index finger. You have now 5 in your hand. [Combination applied +4 = +5 – 1]

Step 3 To add 4, open four fingers of unit hand

Answer is 9.

47 + 1 – 1 + 40

Step 1 To add 47, open tens hand’s 4 fingers and unit hand’s thumb, index & middle finger

Step 2 To add 1, open ring finger of unit hand. You have now 48 in your hand.

Step 3 To subtract 1, close ring finger of your unit hand. You have now 47.

Step 4 To add 40, open thumb of tens hand and close little finger of tens hand. You have now 87. [Combination applied +4 = +5 – 1]

Answer is 87.

3 + 3 – 1

Step 1 To add 3, open index, middle & ring finger of unit hand

Step 2 To add 3, need to open Thumb (5) and close ring & middle finger. You have now 6 in your hand. [Combination applied +3 = +5 – 2]

Step 3 To subtract 1, close index finger of unit hand

Answer is 5.

EXAMPLE (ABACUS)

2 + 4 + 3

Step 1 To add 2, move up 2 beads from lower deck of unit column

Step 2 To add 4, move down 5 from upper deck and move down 1 bead from lower deck. You have now 6. [Combination applied +4 = +5 – 1]

Step 3 To add 3, move up 3 beads from lower deck of unit column.

Answer is 9

3 + 3 – 5

Step 1 To add 3, move up 3 beads from lower deck of unit column

Step 2 To add 3, move down 5 from upper deck and move down 2 beads from lower deck. You have now 6. [Combination applied +3 = +5 – 2]

Step 3 To subtract 5, move up 5 from upper deck of unit column.

Answer is 1.

CLASS WORK 1A

Now you are ready to do sums from your book.

3.1 & 3.2 try to finish this portion within 25 min.

3.3 & 3.4 try to finish this portion within 25 min.

BEADS DRAW

How to draw 21

Step 1 Draw an answer line with a straight horizontal line

Step 2 Draw unit column

Step 3 Draw tens column

Step 4 Draw two circles on tens column’s lower deck and one circle on the unit column’s lower deck touching the answer line

In this way guide your child to draw 21 to 40.

ORAL CALCULATION

Oral calculation is very important for increasing concentration and hearing skill. For oral sums parents will use Hearing Exercise Book. In this week students will use their fingering and abacus to do calculation and write the answers in Exercise 1 to 4 of week 3.

HOME WORK 1 B.1

The home work will be 1B.1 page 3 & 4

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