You have to multiple 6 times itself to get the sides
Givens
Petri Dish A sees a double ever 10 minutes
Petri Dish B sees a double ever 6 minutes
Consequences
A doubles 60 / 10 = 6 times.
B doubles 60 / 6 = 10 times.
Solution
If you work best with numbers then suppose there are 100 bacteria in both dishes at the beginning
A = 100 * 2^6
B = 100 * 2^10
A will have 100 * 64 = 6400 bacteria growing inside A
B will have 100 * 1024 = 102400 bacteria growing inside B
B/A = 102400 / 6400 = 16
There are 16 times as many in B than in A. <<<< Answer
I believe it is 8,000 grams :).