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Question 19

Write an example for each of the scenarios shown in the diagram whenever possible.

Question diagram 1
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Solution

We will find an example for each scenario or explain why it is not possible.

Step 1 — First addition scenario

We need two 5-digit numbers. Their sum must be a 5-digit number. This sum must be more than 90,250.

45,123+46,00045,123 + 46,000

=91,123= 91,123

45,123+46,000=91,123\boxed{45,123 + 46,000 = 91,123}

Diagram 1

Step 2 — Second addition scenario

We need a 5-digit number and a 3-digit number. Their sum must be a 6-digit number.

99,800+25099,800 + 250

=100,050= 100,050

99,800+250=100,050\boxed{99,800 + 250 = 100,050}

Diagram 2

Step 3 — Third addition scenario

We need two 4-digit numbers. Their sum must be a 6-digit number. The largest 4-digit number is 9,999. The largest possible sum of two 4-digit numbers is 9,999 + 9,999 = 19,998. A 6-digit number must be at least 100,000. Since 19,998 is smaller than 100,000, this is not possible.

Not possible\boxed{\text{Not possible}}

Diagram 3

Step 4 — Fourth addition scenario

We need two 5-digit numbers. Their sum must be a 6-digit number.

50,000+50,00050,000 + 50,000

=100,000= 100,000

50,000+50,000=100,000\boxed{50,000 + 50,000 = 100,000}

Diagram 4

Step 5 — Fifth addition scenario

We need two 5-digit numbers. Their sum must be exactly 18,500. The smallest 5-digit number is 10,000. The smallest possible sum of two 5-digit numbers is 10,000 + 10,000 = 20,000. Since 18,500 is smaller than 20,000, this is not possible.

Not possible\boxed{\text{Not possible}}

Diagram 5

Step 6 — First subtraction scenario

We need two 5-digit numbers. Their difference must be less than 6,503.

15,00010,00015,000 - 10,000

=5,000= 5,000

15,00010,000=5,000\boxed{15,000 - 10,000 = 5,000}

Diagram 6

Step 7 — Second subtraction scenario

We need a 5-digit number and a 3-digit number. Their difference must be a 4-digit number.

10,00010010,000 - 100

=9,900= 9,900

10,000100=9,900\boxed{10,000 - 100 = 9,900}

Diagram 7

Step 8 — Third subtraction scenario

We need a 5-digit number and a 4-digit number. Their difference must be a 4-digit number.

10,0001,00010,000 - 1,000

=9,000= 9,000

10,0001,000=9,000\boxed{10,000 - 1,000 = 9,000}

Diagram 8

Step 9 — Fourth subtraction scenario

We need two 5-digit numbers. Their difference must be a 3-digit number.

10,10010,00010,100 - 10,000

=100= 100

10,10010,000=100\boxed{10,100 - 10,000 = 100}

Diagram 9

Step 10 — Fifth subtraction scenario

We need two 5-digit numbers. Their difference must be exactly 91,500. Let the first 5-digit number be AA and the second be BB. The largest 5-digit number is 99,999. The smallest 5-digit number is 10,000. The largest possible difference between two 5-digit numbers is 99,999 - 10,000 = 89,999. Since 91,500 is greater than 89,999, this is not possible.

Not possible\boxed{\text{Not possible}}

Diagram 10

Answer

(i) 45,123+46,000=91,12345,123 + 46,000 = 91,123 (ii) 99,800+250=100,05099,800 + 250 = 100,050 (iii) Not possible (iv) 50,000+50,000=100,00050,000 + 50,000 = 100,000 (v) Not possible (vi) 15,00010,000=5,00015,000 - 10,000 = 5,000 (vii) 10,000100=9,90010,000 - 100 = 9,900 (viii) 10,0001,000=9,00010,000 - 1,000 = 9,000 (ix) 10,10010,000=10010,100 - 10,000 = 100 (x) Not possible

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