Page 81 - Revised Maths Wisdom Class - 1

Additi on of 2-Digit Numbers 79

Look at these marbles in the Now, we can put 3 under the tens
three groups of ten that is 10 place as we have 3 groups of 10.
plus 10 plus 10 are equal to 30.

Now, see! Only 5 marbles are left. It is your turn.
Where and what should we put under the ones place?

Didi, we have left with 5 marbles and these
can’t be added up to one more group of 10.

Amazing!!!
I knew you
can do it.

Definitely, these will be put It means I have 35 marbles. Thanks
under the ones place as 5. didi to teach me this useful concept.

Divide the class into groups of four. Use two abacuses to obtain the sum of two numbers,
for example, 44 and 32. Ask one student to set 4 beads on the tens place and 4 beads on the
ones place of the first abacus. Ask a second student to place 3 beads in the tens place and 2
beads in the ones place on the second abacus to equal 32. One of the other two students in
the group will now count the total number of beads in tens and ones places of both abacuses to obtain the sum.
Now, ask the class to write down the sum of the given numbers using the abacuses in the same manner.