a. Based on the information provided, it is not possible to predict if there are more red marbles or more brown marbles in the bowl, because the sample size is not given. It is possible that the sample is not representative of the overall population of marbles in the bowl, and thus the sample proportions may not accurately reflect the actual proportions of red and brown marbles in the bowl.
b. To determine the probability of picking a red or brown marble from the bowl, we need to know the overall proportion of red and brown marbles in the bowl. From the given sample, we know that the proportion of red marbles is 18/45 or 0.4, and the proportion of brown marbles is 27/45 or 0.6. Assuming that these proportions are representative of the overall population of marbles in the bowl, we can predict that we are more likely to pick a brown marble (with a probability of 0.6) than a red marble (with a probability of 0.4) if we pick one marble from the bowl.