







The tens digit of a number is five times the unit digit 
20160519 

From sanjeev: The tens digit of a number is five times the unit digit. Find the number? Answered by Penny Nom. 





The units digit of a prime 
20150108 

From Patricia: Every prime number greater than 10 has a digit in the ones place that is included in which set of numbers below 1 3 7 9 or 1 3 7 or 0 2 4 5 6 8 or 1 3 5 9 Answered by Walter Whiteley. 





Units digit 
20140103 

From gracie: 9^23 units digit Answered by Penny Nom. 





The units digit 
20120911 

From Shaunice: Simplify each of the following expressions and determine what the last
digit would be.
a. (24^15) 4 Answered by Penny Nom. 





The units digit of a prime number 
20111122 

From Mike: Every prime number larger than 10 has a digit in the ones place that is included in which set of numbers below?
A. 1,3,7,9
B. 1,3,5,9
C. 0,2,4,5,6,8
D. 1,3,7 Answered by Penny Nom. 





A two digit number 
20110301 

From jhoanna: the sum of the digits of a two digit number is 10. The value of the number is 16 times the units digit.Find the number. Answered by Penny Nom. 





Units digit 
20090723 

From Jyll: How do solve for the units digit? And that, what is the units digit of the first 1000 prime numbers? Answered by Robert Dawson. 





Units digit 
20090415 

From A student: What is the unit digit of 47 to the 43rd power? Please answer as soon as possible. Thank you. Answered by Stephen La Rocque. 





The units digit of 2^95 
20090318 

From Sharvon: what is the units digit of 2^95 Answered by Robert Dawson. 





The units digit is 5 
20090202 

From Ray: the number that when squared the units digit is 5 Answered by Penny Nom. 





The 2 rightmost digits 
20081218 

From Peter: Is there a pattern for the 2 rightmost digits of a power? For example, one problem for a math competition was what are the 2 rightmost digits of 3^1993? Answered by Robert Dawson and Victoria West. 





The units digit of (7*3)^21 
20080716 

From surender: what will be the unit digit of (7*3)^21?plz give me method 2 calculate such problems.thank you. Answered by Penny Nom. 





Units digit 
20080702 

From seemachauhan: How to find unit digit of various numbers and what are unit digits? Answered by Penny Nom. 





Units digit 
20080111 

From Robin: hello  my question is:
what is the units digit of (13) to 4; (17) to 2 and (29) to 3
[(13)4(17)2(29)3]
(possible answers: 9 or 7 or 5 or 3 or 1) Answered by Penny Nom. 





The sum of the ones 
20071029 

From Hangsun: When 2 two digit numbers are added what is the greatest possible sum of the ones? Answered by Penny Nom. 





The units digit of 23^45 + 67^89 
20070816 

From Christopher: What is the units digit of 23 to the 45th power plus 67 to the 89th power? Answered by Stephen La Rocque. 





The units digit of 9^2006 + 3^2006 
20070130 

From Ryan: What is the units digit of the sum of 9^2006 and 3^2006 Answered by Penny Nom. 





The units digit 
20070109 

From Tyrone: This may be a dumb question, but what is the unit digit of two digits, eg: 62 or 13 or 45. Answered by Steve La Rocque and Diane Hanson. 





The units digit of 1^5 + 2^5 + ... + 2006^5 
20061114 

From Lana: Compute the unit's digit of : 1 to the power of 5 + 2 to the power of 5 + 3 to the power of 5 + 4 to the power of 5 + 5 to the power of 5 + 6 to the power of 5 + ... + 2006 to the power of 5 . Answered by Stephen La Rocque and Penny Nom. 





The units digit 
20060305 

From Taran: My teacher asked: What is the unit's digit in the product 5 X 10 X 15 X 20 X 25? What is a "unit's digit", what are they asking for? Answered by Penny Nom. 





What is the unit's digit? 
20051004 

From Alex:
Question: What is the unit's digit of the following problem?
3^{155} + 7^{412} (3 to the 155th power + 7 to the 412th power.)
Answered by Penny Nom. 





n^2+n1 has no divisors ending with 3 or 7 
20050908 

From Arne: at least it seems like for any integers n and k,
10k+3 and 10k+7 do not divide nē+n1
I tested this for every n from 0 to 3200 (which means same for the numbers from 3201 to 1)
could this be true, or is it just coincidence, or am I just totally wrong? Answered by Richard McIntosh. 





The last digit of a large exponent 
20041020 

From Landon: How can one determine the last digit of a large exponent by hand. I have seen several examples of how to do this by breaking it up into smaller exponents, but is there a formula or some common things to look for? Answered by Penny Nom. 





The last digit of 2^28 
20040925 

From A student: I am currently enrolled in a math reasoning class and a math question I have to answer is determine the units digit in 3 28power. When I set up a table and keep cubing the numbers, I find a pattern with the last digits of the numbers that follow 1,3,9,7. My calculator gets to about the 19th power, and then I get an error. If I continued the pattern, would the units digit then be the last digit of 3 28th power, which would be a 7? Please let me know if I am solving this correctly and what a unit's digit actually is. Answered by Penny Nom. 





The units digit of 57 to the 28th power 
20030901 

From Maria:
If 57 is raised to the 28th power, what must be the units digit in the result? If you raise 7 to the 500th power, what is the numeral that will appear in the units digit position? Answered by Penny Nom. 





The units digit of 2 to the power of 31921 
20021218 

From A student: If 2 to the power of 31921 is multiplied out, what will be the units digit? Answered by Penny Nom. 





The units digit of 3 to the 58th power 
20000510 

From Kylie Mcalpine: the questions we have been asked are what is the units digit of the following: a) 3^{58} b) 23^{58} c) 17^{31} and the harder question of: what is the units digit of the following sum: 13^{841} + 17^{508} + 24^{617} = ??????? Answered by Paul Betts and Penny Nom. 

