Aggregate is the total amount of goods and services available in the economy at all possible price levels.

Well if it was 8 hours in the morning and 7 in the evening per day of the week it would be 105 divided by 2 for the number of sessions would equal to 52.5 sessions. if it was just that amount of time from that whole week, it would be 15 hours divided by 2 which would give you 7.5... Did that help?