Identify the interval that is not equal to the other three. explain your reasoning. (intervals are 15-19; 30-34; 40-45; 45-49)

This doesn’t make sense to me it’s supposed to be lcm ( least common multiple )

Plz help plz give me the answer

Which of these equations, when solved, gives a different value of x than the other three? a9.1 = -0.2x + 10 b10 = 9.1 + 0.2x c10 – 0.2x = 9.1 d9.1 – 10 = 0.2x