We notice that the common ratio of teh sequence is 10, and that the first term is -0.56, then the recursive formula is:
1 1/2 or 3/2 because there is 4 more than 8 which is a half.
Time 15.625 to the 3 and divide it by 10.00 grams and you will get your answer
The answer to this equation would be 3.