What is the number of ones digit when you multiply 27 50 times ?
Answer
The number of ones digit is to be in a cycle of 7-9-3-1.
Calculate the number of this cycle in 50 times which is 50/4=12 cycles and remainder 2.
Since remainder is 2, the number of ones digit at 50 times multiplication is the second number of the cycle which is 9.
9
Solution
You should focus on the number of ones digit even if two digits number is multiplied.
The number of ones digit is to be in a cycle of 7-9-3-1.
Calculate the number of this cycle in 50 times which is 50/4=12 cycles and remainder 2.
Since remainder is 2, the number of ones digit at 50 times multiplication is the second number of the cycle which is 9.
