One gram of a certain health food contains 7 percent of the minimum daily requirement of vitamin E and 3 percent of minimum daily requiremet of vitamin A. If vitamins E and A are to be obtained from no hter source, approximately how may grams of the grams of hte health food must be eaten daily to provide at least minimum daily requirement of both vitamins?

33.  问题是不少了一个条件, 每天的vitamin的需求量是多少?

7% of the minimum requirement of E is present in 1 gram
=> Minimum requirement of E (100%) is present in 100*1/7 = 14.3 gms
so if only vitamin E was the constraint then 14.3 gms would have been enough.

Now look at Vitamin A.
3% of the minimum requirement of A is present in 1 gram
=> Minimum requirement of A (100%) is present in 100*1/3 = 33.3 gms

=> 14.3 is enough for minimum requirement of E but not A. to satisfy both we need to have 33.3 grams.

So, Answer is 33 grams.