Bunuel wrote:
A zoo has twice as many zebras as lions and four times as many monkeys as zebras. Which of the following could be the total number of zebras, lions, and monkeys at the zoo?
I. 22
II. 55
III. 121
A. I only
B. II only
C. III only
D. I and III only
E. I, II and III
We can create the equations:
Z = 2L
Z/2 = L
and
M = 4Z
Thus, the total is Z + Z/2 + 4Z = 5Z + Z/2 = 10Z/2 + Z/2 = 11Z/2
Lets test each Roman numeral to see if an integer results:
I.
22 = 11Z/2
44 = 11Z
4 = Z
This works.
II.
55
...
