7 tens
Ten-Groups = 10 + 10 + 10 + 10 + 10 + 10 + 10
Ten-Groups = 70
1 ones
71 = 0 Hundreds + 70 Tens + 1 ones
71 = 0 + 70 + 1
Show numerical properties of 71
71
seventy one
Decompose 71
Each digit in the whole number represents a power of 10:
Take the whole number portion on the left side of the decimal
Expanded Notation of 71 = (7 x 101) + (1 x 100)
Expanded Notation of 71 = (7 x 10) + (1 x 1)
71 = 70 + 1
71 = 71 <---- Correct!
Make blocks of 5
1 tally mark = |
2 tally marks = ||
3 tally marks = |||
4 tally marks = ||||
5 tally marks = | | | |
5 = | | | |
10 = | | | |
15 = | | | |
20 = | | | |
25 = | | | |
30 = | | | |
35 = | | | |
40 = | | | |
45 = | | | |
50 = | | | |
55 = | | | |
60 = | | | |
65 = | | | |
70 = | | | |
71 = |
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Define an ordinal number
A position in a list
71st
Calculate the digit sum of 71
Calculate the reduced digit sum of 71
Digit Sum → 7 + 1 = 8
Since our digit sum ≤ 9:
we have our reduced digit sum
Digit Sum → 7 + 1 = 8
Calculate the digit product of 71
Digit Product = Value when you multiply
all the digits of a number together.
We multiply the 2 digits of 71 together
Digit product of 71 = 7 * 1
Digit product of 71 = 7
Opposite of 71 = -(71)
Opposite of = -71
Place value describes each digit
7 is our tens digit
This means we have 7 sets of tens
1 is our ones digit
This means we have 1 sets of ones
7 is our tens digit
1 is our ones digit
When ey = x and e = 2.718281828459
We have Ln(x) = loge(x) = y
Ln(71) = loge(71) = 4.2626798770413
Is 71 divisible by:
2,3,4,5,6,7,8,9,10,11
Last digit ends in 0,2,4,6,8
The last digit of 71 is 1
Since 1 is not equal to 0,2,4,6,8:
then 71 is not divisible by 2
Sum of the digits is divisible by 3
The sum of the digits for 71 is 7 + 1 = 8
Since 8 is not divisible by 3:
Then 71 is not divisible by 3
Take the last two digits
Are they divisible by 4?
The last 2 digits of 71 are 71
Since 71 is not divisible by 4:
Then 71 is not divisible by 4
Number ends with a 0 or 5
The last digit of 71 is 1
Since 1 is not equal to 0 or 5:
Then 71 is not divisible by 5
Divisible by both 2 and 3
Since 71 is not divisible by 2 and 3:
Then 71 is not divisible by 6
Multiply each respective digit by 1,3,2,6,4,5
Work backwards
Repeat as necessary
1(1) + 7(3) = 23
Since 23 is not divisible by 7:
Then 71 is not divisible by 7
Take the last three digits
Are they divisible by 8
The last 2 digits of 71 are 71
Since 71 is not divisible by 8:
Then 71 is not divisible by 8
Sum of digits divisible by 9
The sum of the digits for 71 is 7 + 1 = 8
Since 8 is not divisible by 9:
Then 71 is not divisible by 9
Ends with a 0
The last digit of 71 is 1
Since 1 is not equal to 0:
Then 71 is not divisible by 10
Σ odd digits - Σ even digits = 0
or 71 is a multiple of 11
71
7
Odd Sum = 7
71
1
Even Sum = 1
Δ = Odd Sum - Even Sum
Δ = 7 - 1
Δ = 6
Because Δ / 11 = 6.4545454545455:
Then 71 is NOT divisible by 11