In a random sample of 120 adults who identified a favorite sport, how many of them consider soccer their favorite sport?
(1) In the sample, the number of adults who do not consider soccer their favorite sport is twice the number of adults who consider soccer their favorite sport.
(2) In the sample, the number of adults who consider soccer their favorite sport is 40 less than the number of adults who do not consider soccer their favorite sport.
Interpret: I did not write the equation, or solve the equation that makes both pieces of information SUFFICIENT to solve this problem. Both are sufficient b/c both identify an equation that is solvable and does not have too many variables to solve it.
Here are the equations for those wondering minds:
(1) 120 adults
--Two groups: Soccer IS their FAV. Let's give this group the variable "F" standing for the NUMBER of adults who claim soccer IS their Favorite sport.
--Soccer is NOT their Fav. Let's give this group the variable "N" for NOT!
N = 2F
N + F = 120 (Don't forget this equation---> it is often identified as the parts equal the whole.)
This is solvable with the system of equations given. Sufficient!
(2) F = N - 40
and once again, N + F = 120
Again, a solvable system of equations. Sufficient!
D, Both are sufficient