#### Answer

The conclusion does not follow the premises.

#### Work Step by Step

The Euler's circles for the first statement involve the circle for Boys being inside the circle for Ride Bikes.
The Euler's circles for the second statement involve the circle for Americans being inside the circle for Ride Bikes.
Note, however, that some Americans are not Boys and some Boys are not American.
Thus, the circles for Boys and Americans overlap.
The diagram will involve three circles:
(1) One circle, which is inside the circle that represents Ride Bikes, represents the Boys.
(2) One circle, which is inside the circle that represents Ride Bikes, represents Americans.
(3) The biggest circle, which contains both circles in (1) and (2) above, represents Ride Bikes.
(Refer to the diagram in the answer part above.)
The diagram shows that NOT all American are Boys.
Thus, the conclusion does not follow the premises.