Q: how many members are 35 or older?

We think: value question asking us to solve for an actual number, so we need info about numbers!

1) nothing about actual numbers (i.e. just a fraction) - insufficient.

2) nothing about age breakdown - insufficient.

Eliminate A, B and D.

Together: (2) gives us a percent and a part, so we can figure out the whole, i.e. total number of members. Now we can use (1) to calculate how many members are 35 or older.

Together sufficient, choose (C)!

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Thanks & Regards,

Anaira Mitch