3. Give and Take

I am Kittu. This is my home. Isn't it huge? It has 100 rooms. Help me in painting some of the rooms.

I start from room 2. I add 10 to 2 to reach room 12 and paint it. To add 10 to 2, we can go all the way to the right to 10.

Then up to 11, and one step right to 12.

This is one way to go from 2 to 12.

Is there a shortcut? Of course! Follow me.

We can jump up one row.

A jump from 2 to 12 is like taking _____ steps.

Now try one jump up from 14.

14 + 10 = 24.

Colour this room.

How will I go from 22 to 41?

Jump from 22 to 42.

Then one step left. We can write it like this.

22 + 20 = 42

42 – 1 = 41

How many steps did I go in all? _____

You could also go this way:

From 22 take one step left to 21.

Then two jumps up to 41.

22 – 1 = 21

21 + 20 = 41

Find My Food

Try these on Kittu's home:

Hey! I have something more interesting for you.

Ma told me, there are sweets to eat in some rooms.

Help me find that room. The answers from the next page will help you find that room. Mark them in my home.

a) 10 less than 34 is _____.

b) 53 – 20 = _____.

c) 11 more than 31 is ______.

d) 11 less than 66 is _____.

e) 62 + 13 = _____

f ) 23 less than 89 is  _____.

g) 10 and 40 more is _____.

h) 9 added to 28 gives _____.

i) The sum of 9 and 44 is _____.

j) Reducing 98 by 34 gives _____.

k) 4 and 37 more is _____.

l) Take 35 away from 83. We get _____.

E.g., 47 = 37 + 10

37 + 9 = _____

Is there a shortcut to do this?

65 – 30 = _____

_____ = 46 + 21

_____ = 87 – 30

66 – _____ = 11

36 = ____ + 9

45 + ____ = 99

40 + ____ = 76

____ + 26 = 75

98 = ____ + 50

____ – 21 = 35

57 – ____ = 20

Adding Made Easy

Anisha bought apples for 37 rupees. Raja bought bananas for 21 rupees. The woman selling fruits said:

37 is 30 and 7

21 is 20 and 1

So 37 and 21 make 58.

The first two, I can do.

How did she add 37 and 21 so fast?

• Let us also try. Look at this sum.
  

We break 26 into 20 + 6 and 43 into 40 + 3.

Then it's easy: we add 20 + 40 and 3 + 6!

The answer is 69.

• Can you do it another way? Say how.
  

See if you can do the same with these sums.

MANGO CHILLI GAME

Roll a pair of dice and move by adding the numbers that come on the top of both the dices.

Keep a different coloured button for each player. If you reach a mango you go forward (+). If you step on a chilli you have to go back (–). See who reaches back home first!

56 + 21 = 56 + 20 + 1

= 57 + 20

= 77

Aha!

I can do it this way also!

Now work out the steps in your mind.

Write the answers directly in the boxes.

33 + 42 = _____

_____ = 33 + 27

55 + 25 = _____

19 + 61 = _____

_____ = 34 + 63

67 + 25 = _____

_____ = 48 + 42

_____ = 53 + 64

72 + 56 = _____

Let Me Tell You a Story..........

Once a baby lion lost his way in the jungle. He started crying and called out for his mother. An old deer took pity on him. He took him to his place. But the other deer got really scared. So did their other friends - rabbits, squirrels and birds. A lion among us! Oh, no! He will eat up our babies. The old deer said - don't worry. I will warn him about this. In the morning the baby lion thanked every one and started to leave. But a rabbit said - wait, he cannot go like this! Let us count to see if he has done any mischief. We should be 240 in all. Let's count.

Tillu counted rabbits and deer. There were 27 rabbits and 48 deer

The old deer counted birds and squirrels. There were 124 birds and 38    Squirrels.

In the chapter Fun with Numbers, children would have made token cards. The same token cards should be used for exercises in addition before children do written sums.

• Let's add and find out how many deer and rabbits were there...
  

Putting all the  ’s together, we get fifteen  ’s

Ten  ’s make one  ’s and we are left with five  ’s.

Now putting together all the ’s, we get seven ’s

So total number of deer and rabbit = 75

• Similarly we add the number of birds and number of squirrels.
  

So together birds and squirrels were 162, and deer and rabbits were 75.

The old deer said — we were 240 in number, now how many are we in all?

To find out, do the addition in the box below:

Can you guess now, if the baby lion will go back home? Has the baby lion eaten up any animal?

To find out, do the addition in the box below:

How Many Bulbs?

1. A factory made 270 bulbs on the first day. On the second day it made 123 bulbs.

How many bulbs did the factory make altogether?

First day - 270 bulbs

Second day - 123 bulbs

270 + 123

Is the sum more than 350

or less than 350?

I think.. 270 and 100 is 370?

The sum is more than 350.

How many altogether?

Solution:

2. A shopkeeper Rafi had 153 candles. Paras gave him 237 more candles. How many candles does Rafi have now?

237 + 153 =?

Is the sum more than 400 or less than 400?

Solution:

Work out the following story problems in the same way. Read each problem and say it in your words. Guess the answer before writing it.

A. A train compartment is carrying 132 people. Another compartment is carrying 129 people. In all, how many people are there in both the compartments?

B. Shanu found 138 pebbles. Karim found 44 pebbles.How many pebbles did they find in all?

C. A teacher kept a record of, the fruits students like. This is what she found:

Find out:

(a) How many students in the school like oranges?

(b) How many students in the school like mangoes?

(c) Altogether, how many students are there in the school?

(d) Is the number of girls more than 350 or less than 350?

Practice Time

1. 345 + 52
2. 492 + 29
3. 245 + 93
4. 643 + 345
5. 750 + 290

B.

Pu^ZZle

Addition is my best friend

We never have a fight

When I am done

Call out to him

And check if I am right

MIND BUS GAME :

Two friends play this game. You look at the bus. Some people come in (+) and some leave (–) at each bus stop. How many are there in all? Solve in your MIND! Discuss your answer. The friend who gets the right answer first wins some points. List down your points. Add to find who wins the most!

Work out four different ways to write the numbers.

If you add all the numbers in the first box, you will always get 59.

   

   

Can You Solve this Pu^ZZle?

Write the numbers 1, 2, 3, 4, 5, 6 in the circles, so that the sum of the numbers on each side of the figure is 12.

Find Mithoo's Bag

Do all the sums mentally:

a. 75 + 20 = 95  

b. 90 + 60 = 150  

c. 25 + 30 + 3 =........

d. 9 + 40 + 31 =.........

e. 500 + 200 =..........

f. 400 + 350 =...........

g. 670 + 120 =..........

h. 380 + 210 =..........

i. 128 + 600 =...........

j. 205 + 650 =...........

k. 150 + 69 =............

l. 37 + 46 + 3 =..........

Find Mithoo's bag and check your answers.

Draw a line through the numbers which are answers written in the boxes above.

Card Game

One day Bubbly and Gopu were playing. Bubbly gave three number cards  to Gopu. He arranged the cards in two ways.

Can you arrange these cards other than these two ways?

Bubbly arranged them this way:

Isn't it interesting?

You can also play it. Here are the cards for you. Work out the combination. Place the cards in the right boxes.