What is the unit digit in the product (14)^{153} (23)^{84} (625)^{72}?0123
Answers
Answer:
14^153 varies with odd and even number
when exponent is odd unit digit 4
when even unit digit 6
23^84
when power 1 units digit 3
2 9
3 7
4. 1
this will continue
so for power 84 units digit 1
for 625^72
625^1. units digit 5
625^2. 5
also for 625^72 units digit 5
multiply all unit digits
we will get the answer 0
Answer : 0
Explanation :
Unit digit in the product is The product of unit digits in individual terms.
So, To find the unit digit in (14)^{153} × (23)^{84}× (625)^{72} , We need to find unit digits individually and Multiply them over.
So, 14^453
- Unit digit is 4
- It is powered to 453
- Odd power of 4 yields unit digit 4
- Even power of 4 yields unit digit 6.
- Power 453 is odd, so it gives unit digit as 4.
Therefore, Unit digit of 14^453 = 4
Now, (23)^{84}
- Unit digit is 3
- It is powered to 84
- We know that,
- We know that, Unit digits of 3 repeats themselves after 4 time. That is, 3^1 has the same unit digit as 3^4n + 1
- So, 3^84 = 3^4(20)+4
- Unit digit = Unit digit of 3^4 = Unit digit of 81 = 1
Therefore, Unit digit of 3^84 = 1
Now,
625^{75}
- Unit digit is 5.
- It's powered to 75
- We know that, Any Power of 5 yields unit digit 5.
Therefore, Unit digit of 625^75 is 5
Unit digit of the product ; (14)^{153} × (23)^{84}× (625)^{72}
= Unit digit of 4 × 1 × 5
= Unit digit of 20
= 0
Unit digit of the product is 0
Hence, 0 is the required answer!