Sarah put raisins into 3/4 of the oatmeal cookie dough she was making. She put nuts into 2/5 of the oatmeal cookie dough with the raisins. What fraction of the entire batch has BOTH raisins and nuts.
The LCM (lowest common multiple) of 4 and 5 is 20, so convert them so that the denominator is 20:
3/4 = 15/20 2/5 = 8/20
I didn't quite read the question properly, but regardless. Since only 15/20 of the batch has raisins, of which only 8/20 has nuts, we can formulate this equation to solve:
