If the corrugated iron costs $1.75 per m2, how much would it cost to sheet the roof when each actual sheet width is 820 mm?

Find dy/dx using implicit differentiation ln(20+e^xy)=y

How many solutions does the nonlinear system of equations graphed bellow have?

The weekly amount spent by a company for travel has an approximately normal distribution with mean = $550 and standard deviation = $40. a) what is the probability that the actual weekly expense will exceed $570 for more than 20 weeks during the next year? (note: one year = 52 weeks) b) what is the probability that actual weekly expenses exceed $580 for 10 or more, but 16 or fewer weeks during the next year?