Answer:
Jane ate 4/9 of the pizza, Joey ate 1/3 (or 3/9) of the pizza, and Josephine ate 2/9 of the pizza
Explanation:
Let x = the part which Jane ate
y = the part which Joey ate
z = the part which Josephine ate
now Jane ate twice as much as Josephine so,
x = 2z
also, Joey ate 1 1/2 as much as Josephine
Note: 1 1/2 = (2/2)+(1/2) = 3/2
so,
y = (3/2)z
Now,
they ate the whole pizza so,
the part that Jane ate + the part that Joey ate + the part that Josephine ate = 1 whole pizza
or,
x + y + z =1
now, we put the values of x and y into this last equation, we get,

so Josephine ate 2/9 of the pizza
for Jane,
x = 2z,
x = 2(2/9)
x = 4/9
so Jane ate 4/9 of the pizza
For Joey,
y = (3/2)z
y = (3/2)(2/9)
y = 1/3
soJoey ate 1/3 of the pizza