A lake near the Arctic Circle is covered by a 2-meter-thick sheet of ice during the cold winter months. When spring arrives, the warm air gradually melts the ice, causing its thickness to decrease at a constant rate. After 3 weeks, the sheet is only 1.25 meters thick. Complete the equation for the relationship between the thickness and number of weeks.
Q. A lake near the Arctic Circle is covered by a 2-meter-thick sheet of ice during the cold winter months. When spring arrives, the warm air gradually melts the ice, causing its thickness to decrease at a constant rate. After 3 weeks, the sheet is only 1.25 meters thick. Complete the equation for the relationship between the thickness and number of weeks.
Given Information: We know:Initial thickness of the ice: 2 metersThickness after 3 weeks: 1.25 metersDuration: 3 weeksWe need to find the rate at which the ice thickness decreases per week.
Calculate Rate of Decrease: To find the rate of decrease per week, we subtract the final thickness from the initial thickness and then divide by the number of weeks.Rate of decrease per week = (Initial thickness−Final thickness)/DurationRate of decrease per week = (2meters−1.25meters)/3weeks
Calculate Rate per Week: Now we calculate the rate of decrease per week.Rate of decrease per week = (0.75meters)/3weeksRate of decrease per week = 0.25meters per week
Equation for Relationship: The equation for the relationship between the thickness T of the ice and the number of weeks w is:T=Initial thickness−(Rate of decrease per week×w)T=2meters−(0.25meters/week×w)
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