What is the units’ digit of the following expression 13^5*15^4*17^5

Question

What is the units’ digit of the following expression  13^5*15^4*17^5 ?

A. 0
B. 1
C. 3
D. 5
E. 9

Archit3110 · Answer

13^5 ; 3
15^4 ; 5
17^5; 7
3*5*7 ; 5
IMO D

chrtpmdr · Answer

Repeating Patterns

13 ^5 = 3 / 9 / 7 / 1 /  3  ......
15 ^4 = 5 / 5 / 5 /  5 
17 ^5 = 7 / 9 / 3 / 1 /  7  ...

3*5*7 = ...5

ScottTargetTestPrep · Answer

Since 3^5 has a units digit of 3, since 5^4 has a units digit of 5, and since 7^5 has a units digit of 7, the units digit of the given product is the units digit of 3 x 5 x 7 = 105 or 5.

Answer: D

Kinshook · Answer

Asked: What is the units’ digit of the following expression  13^5*15^4*17^5 ?

Unit digit of 3^5*5^4*7^5
= unit digit of 3*5*7=5

IMO D

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rxb266 · Answer

Since we have a number that ends with digit 5, the product shall have uniti digit as 0 if one of the numbers is even and 5 if all the numbers in product are odd.

In the given expression , 13 15 and 17 are odd numbers. Hence the unit digit of the number obtained is 5. OPTION C

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Abhishek009 · Answer

13^5  will have units digit as  3 
 15^4  will have units digit as  5 
 17^5  will have units digit as  7

So, The units digit of  13^5*15^4*17^5 = 3*5*7 = 5 , Answer must be (D)

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What is the units’ digit of the following expression 13^515^417^5

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