one more, please help

Alynna and Christel went shopping together with a total of $750. Alynna spent 1/3 as much as Christel.

They saved the rest of their money.  Alynna spent $148 less than what she had saved. 

In the end , she saved twice as much money as Christel.

a) How much money did Alynna spend?

b) How much money did Christel have at first?