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Question 3

Fill the table below such that we get as many supercells as possible. Use numbers between 100 and 1000 without repetitions.

Question diagram 1
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Solution

FIO-3

Chapter: NUMBER PLAY
Class: 6 (Class 6)
Category: figure_it_out


Question

Fill the table below such that we get as many supercells as possible. Use numbers between 100 and 1000 without repetitions.

Question diagram(s):

Question diagram


We must find the rule for "supercells" from the example.

Step 1 — Finding the Supercell Rule

We look at the supercells: 999, 555, 666, 498, 501. We look at the non-supercells: 101, 444, 298, 397. We check for divisibility by 3. We add up the digits of each number. If the sum divides by 3, the number divides by 3.

For supercells: 9+9+9=279+9+9 = 27 27 divides by 3. 5+5+5=155+5+5 = 15 15 divides by 3. 6+6+6=186+6+6 = 18 18 divides by 3. 4+9+8=214+9+8 = 21 21 divides by 3. 5+0+1=65+0+1 = 6 6 divides by 3. All supercells divide by 3.

For non-supercells: 1+0+1=21+0+1 = 2 2 does not divide by 3. 4+4+4=124+4+4 = 12 12 divides by 3. 2+9+8=192+9+8 = 19 19 does not divide by 3. 3+9+7=193+9+7 = 19 19 does not divide by 3.

All supercells divide by 3. Most non-supercells do not divide by 3. But 444 divides by 3. Yet 444 is not a supercell. So, a supercell divides by 3. It is also not the number 444. Numbers must be between 100 and 999.

Diagram 1

Step 2 — Filling the Table and Identifying Supercells

We will fill the table with the given numbers. The numbers are: 999, 101, 555, 444, 666, 298, 498, 397, 501. Now we check each number using our supercell rule.

For 999: Sum of digits is 27. 27 is divisible by 3. It is not 444. So, 999 is a supercell.

For 101: Sum of digits is 2. 2 is not divisible by 3. So, 101 is not a supercell.

For 555: Sum of digits is 15. 15 is divisible by 3. It is not 444. So, 555 is a supercell.

For 444: Sum of digits is 12. 12 is divisible by 3. It IS 444. So, 444 is not a supercell.

For 666: Sum of digits is 18. 18 is divisible by 3. It is not 444. So, 666 is a supercell.

For 298: Sum of digits is 19. 19 is not divisible by 3. So, 298 is not a supercell.

For 498: Sum of digits is 21. 21 is divisible by 3. It is not 444. So, 498 is a supercell.

For 397: Sum of digits is 19. 19 is not divisible by 3. So, 397 is not a supercell.

For 501: Sum of digits is 6. 6 is divisible by 3. It is not 444. So, 501 is a supercell.

We have found 5 supercells in the table. The supercells are 999, 555, 666, 498, and 501.

Answer

(i) The filled table is: [999, 101, 555, 444, 666, 298, 498, 397, 501]. (ii) The supercells are: 999, 555, 666, 498, 501. (iii) There are 5 supercells in this table.

More questions in FIO

Q1

Colour or mark the supercells in the table below.

Q2

Fill the table below with only 4-digit numbers such that the supercells are exactly the coloured cells.

Q3

Fill the table below such that we get as many supercells as possible. Use numbers between 100 and 1000 without repetitions.

Q4

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Q5

Find out how many supercells are possible for different numbers of cells.

Do you notice any pattern? What is the method to fill a given table to get the maximum number of supercells? Explore and share your strategy.

Q6

Can you fill a supercell table without repeating numbers such that there are no supercells? Why or why not?

Q7

Will the cell having the largest number in a table always be a supercell? Can the cell having the smallest number in a table be a supercell? Why or why not?

Q8

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Q9

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Q10

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Q11

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Q12

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Q13

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Q14

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a. the difference between the largest and smallest numbers greater than 50855085.

b. the difference between the largest and smallest numbers less than 50855085.

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Q16

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Q17

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Q18

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Q19

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Q20

Always, Sometimes, Never?

Below are some statements. Think, explore and find out if each of the statement is 'Always true', 'Only sometimes true' or 'Never true'. Why do you think so? Write your reasoning and discuss this with the class.

a. 5-digit number + 5-digit number gives a 5-digit number

b. 4-digit number + 2-digit number gives a 4-digit number

c. 4-digit number + 2-digit number gives a 6-digit number

d. 5-digit number – 5-digit number gives a 5-digit number

e. 5-digit number – 2-digit number gives a 3-digit number

Q21

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Q22

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Q23

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Q24

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Q25

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Q26

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Q27

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Q28

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Q29

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Q30

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Q31

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Q32

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Q33

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