ONE + FOUR = FIVE
ONE * 4 = FOUR

In the equations above, each word represents a number in base 10.
In each word, the right most letter is a digit in the ones place, the next digit to the right is in the tens place and the so on.
So for example in the word "ONE" the letter "E" is in the ones place, the letter "N" is in the tens place and the letter "O" is in the hundreds place.

What is the most likely digit represented by the letters and R ?

Response: