Page 188 - ICSE Math 4

(b) In the given number pa ern the rule followed is to double the number
each me or mul ply the previous number by 2.

2 4 8 16 32 64 _____

×2 ×2 ×2 ×2 ×2 ×2
Therefore, the required number in the given pa ern is 64 × 2 = 128.

Number towers

Numbers can also be arranged as a tower. Look at the number tower 28
given alongside. 12 16

Here, 5 + 7 = 12, 7 + 9 = 16 and 12 + 16 = 28. 5 7 9

The rule here is to consider the fi rst two blocks given at the bo om and add the numbers
given in these blocks to obtain the sum which is wri en in the block placed just above
these blocks.

Let’s see another number tower that is fi lled using the same rule. 40

2 + 4 = 6; 4 + 6 = 10; 6 + 8 = 14 16 24
6 + 10 = 16; 10 + 14 = 24
6 10 14
16 + 24 = 40
2 4 6 8
Number patterns with addition

Observe the following number pa erns.

Look at the following three units of a pa ern.
1 + 2 + 3 = 6 2 + 3 + 4 = 9 3 + 4 + 5 = 12

We can see that on adding the fi rst three consecu ve numbers, we obtain 6 as the
sum.

In the second unit, it is observed that each consecu ve number is increased by 1 and the
addi on of these numbers gives the sum as 9.
Similarly, in the third unit, each number of the second unit is increased by 1 and when

these numbers are added together, the sum obtained is 12. Therefore, we can say that the
sum in the above number pa ern is growing by 3 each me.
Now let’s make a pa ern with 5 consecu ve numbers such that their sum grows by 5 each
me.

1 + 2 + 3 + 4 + 5 = 15 2 + 3 + 4 + 5 + 6 = 20 3 + 4 + 5 + 6 + 7 = 25

Reducing Number Pattern

In a reducing number pa ern, the pa ern decreases due to the reduc on of a number or
element from the exis ng sequence. Let’s understand this with the help of an example.

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