Mary worked from Monday to Saturday last week and bought lunch in the company’s restaurant every day. Her lunches cost a different amount every day. Each lunch cost a multiple of 20¢. The most expensive lunch of the week cost $7.60 and the cheapest one cost $4.40. Friday’s lunch cost exactly 1 1/2 times as much as Wednesday’s lunch. Tuesday’s lunch cost $1.20 more than Thursday’s lunch. (a) What is the minimum total that Mary’s six lunches last week could have cost?

(b)What is the maximum total that Mary’s six lunches last week could have cost?

Like many students at university, you may be unhappy about the results you attain in exams. you may feel that even with all you are doing there must be something more -- or different-- you could be doing to get better grades. we have all at some time or other heard of that student who only studies a couple of hours for final exams and scores a's every time. we stand in awe of those who seem to breeze through without undue effort and seem to need very little in the way of studying to nail an exam. the reasons for success, in what i think are the vast majority of cases, are less esoteric than many students think: successful students consistently apply a series of productive strategies with view to attaining clearly identified learning and grade goals throughout the academic term.

Geographic information system
global positioning system
one has the word information, the other has the word positioning