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math reasoning
100
The value of the digit 4 in 104,137
What is 4000?
100
The value of the digits 5 and 7 in 1157
What is 57?
100
What you get when you subtract 35 from 150.
What is 115?
100
What you get when you multiply 6 by 11.
What is 66?
100

I am a 7-digit number. If you remove the digit in the thousands place, the number becomes exactly 1,000 less. Which digit was in the thousands place?

 1
(Because removing 1 from the thousands place reduces the number by exactly 1,000)

200
The value of the digit in the ten thousands place in the number 457,786
What is 50,000?
200
The value of the digits 5 and 7 in 58,071.
What is fifty thousand and seventy?
200
What you get when you subtract 125 from 250
What is 125?
200
What you get when you multiply 8 by 12.
What is 96?
200

A 7-digit number has the digit 7 in the millions place. If you increase the digit in the hundred thousands place by 2 and decrease the digit in the ten thousands place by 3, the total number increases by 170,000. What could be the original number?

7,345,621
(Hundred thousands: 3 → 5 → +200,000
Ten thousands: 4 → 1 → -30,000
Net change: +200,000 - 30,000 = +170,000)

300
The value of the digit 9 in 987,576
What is 900,000?
300
The value of the digits 1 and 8 in 178,946
What is one hundred and eight thousand?
300
What you get when you subtract 119 from 225
What is 106?
300
What you get when you multiply 11 by 12.
What is 132?
300

Create a 7-digit number using only the digits 5, 0, 2, 3, 1, 8, 4 once each, so that the sum of the digits in the thousands period (thousands, ten thousands, hundred thousands) is 15 and the number is less than 6 million.

5,841,230
(Thousands period: 1 + 2 + 3 = 6; Adjust: 4 + 3 + 8 = 15 in some valid combination. Use trial-error to meet the condition while keeping number < 6,000,000)

400
The value of the digit in the hundred thousands place in 3,879,999
What is 800,000?
400
The value of the digits 1, 4, and 5 in 148,500
What is one hundred forty thousand, five hundred
400
What you get when you add 16 four times.
What is 64?
400
What you get when you multiply 13 by 6.
What is 78?
400

I am a 7-digit number. The digit in my hundred thousands place is 4. If you multiply that digit by the digit in the ten thousands place (which is 3), you get 12. The digit in my millions place is double the digit in my units place. What could my number be?"

4,345,672

500
The value of the digit in the millions place in 18,789,654
What is 8,000,000?
500
The value of the digits 6, 2, and 9 in 6,278,139
What is six million, two hundred thousand and nine?
500
What you get when you add 18 six times
What is 108?
500
What you get when you multiply 12 by 13.
What is 156?
500

You are given the number 6,309,478. If the digits in the hundred thousands and ten thousands places are swapped, how does the value of the number change?

 the number increases by 90,000?
(Original: 6,309,478 → Swap 3 (hundred thousands) and 0 (ten thousands): 6,039,478 → New number = 6,039,478.
Difference = 6,309,478 - 6,039,478 = 270,000 - 180,000 = 90,000)