THE arithmetic mean of a date set is 46 and the standard deviation of the set is 4. which value is exactly 1.5 standard deviations from the arithmetic mean of the set?

A 42 B 44.5 C 47.5 D 50 E 52

第二题  A square countertop has a square tile inlay in the center ,leaving an untiled strip of  uniform width around the tile.If the tatio of the tiled area to the untiled area is 25 t 39,which of the following could be the width, in inches, of  the strip?

I .1   II. 3 III. 4

A  .I only  B. II only C.i and iii ONLY  D i and ii only E  i , ii and iii

第三题

怎么都没人理我呢？  拜托各位 我只有一次考GMAT的机会了