Problema Solution
Solve the problem.
A gas station sells 4820 gallons of regular unleaded gasoline in a day when they charge $1.35 per gallon, whereas they sell 3856 gallons on a day that they charge $1.40 per gallon. Find a linear function that expresses gallons sold as a function of price. Use this function to predict the number of gallons sold at a price of $1.29 per gallon.
Answer provided by our tutors
let the function be
y = mx + b,
y = the number of gallons sold
x = the price per gallon
m, b are constants that we need to find
we know that for x1 = 1.35 y1 = 4820 and x2 = 1.40 y2 = 3856 thus we can form the system of equations
4820 = 1.35*m + b
3856 = 1.40*m + b
by solving we find
m = - 19280
b = 30848
click here to see the step by step solution of the equation
thus the function is
y = -19280*x + 30848