Answer:
45-40
Explanation:
The first interval is 15-19.
The width of this interval is: 19-15=4
The second interval is 30-34.
The width of this interval is: 34-30=4
The third interval is 40-45.
The width of this interval is: 45-40=5
The fourth interval is 45-49.
The width of this interval is: 49-45=4
Therefore the interval that is not equal to the other three is 45-40