Question 606789
    i am less than 50.i am greater than 39.my tens digit is 2 more than my ones digit.what number am i?
Let x = number of ones
then
x+2 = number of tens
.
39 < x + 10(x+2) < 50
39 < x + 10x+20 < 50
39 < 11x+20 < 50
.
case 1:
39 < 11x+20
19 < 11x
19/11 < x
1.73 < x
.
case 2:
11x+20 < 50
11x < 30
x < 30/11
x < 2.73
.
We conclude that:
1.73 < x < 2.73
The ONLY integer between the two values is 2
.
Answer: 2