Answer:
Jen ate 18 jujubes
Explanation:
Start with Kim. She was given 10. There is no remainder.
Kyle kept 8 from the total he was given, so Kyle had 18.
Let the number of Jujubes given to Jen = x
(1/2) x = 18 Multiply both sides by 2
2(1/2)x = 18*2
x = 36
Jen ate 1/2 of 36 which was 18.
Though you are not asked, Sam must have begun this with 2*36 = 72 Jujubes.