Hello I was working on some math homework and I was wondering if you could assist me with this question:

You work as an assistant for a professor doing research on sleep deprivation. She has access to a large data set of 15,000 first year students who have all filled out insomnia questionnaires. The scores on this questionnaire are normally distributed and range from 1 to 20. You are part of this data set and recall that your score was 1.4 standard deviations below the mean. If the variance was 3.24 and your raw score was 12.5, what the mean score for the population?