Peter R. answered 12/26/22
Experienced Instructor in Prealgebra, Algebra I and II, SAT/ACT Math.
Here's an answer without using much algebra.
12 is what remains after Ko gave 1/4 of beans to Ad.
so Ko must have had 12 = 3/4 Ko; Ko = 16
Ki gave 1/2 of her beans to Ko, so Ki must have had 16/(1/2), or 32 beans.
Ta gave half of his/her beans to Ki, so Ta must have had 32/(1/2) originally, or 64 jellybeans.
I agree with Raymond B. There's an error somewhere, either in the answer choices or in the question's values.