(mathematics) be divisible / (chiefly in the negative) be resolvable (said of feelings), be convinced (said of the person)

negative of 割り切れる / (arithmetic) be indivisible / be insoluble, be inexplicable / (of a thing) be unconvincing; (of oneself) feel unconvinced

easy / simple, uncomplicated / brief, light, short

ease / simplicity / lightness, brevity

(chiefly in mathematics, physics) for simplicity; for the sake of simplicity

question, problem on homework etc. / a question; a matter (of time etc.) / a problem (something that needs to be dealt with); a trouble / an issue; a matter

(informal) no problem

unthinkable, out of the question

practical question (problem)

matter of life or death / (idiomatic) an extremely urgent matter