Question
You ran out of paint and primer while changing the color tone in your new house. You had already purchased 4 gallons of paint and 9 gallons of primer for a total cost of $275. Back to the paint shop, added 3 more gallons of paint and 5 gallons of primer for $180. Find the cost per gallon for the paint and the pine.
108
likes541 views
Answer to a math question You ran out of paint and primer while changing the color tone in your new house. You had already purchased 4 gallons of paint and 9 gallons of primer for a total cost of $275. Back to the paint shop, added 3 more gallons of paint and 5 gallons of primer for $180. Find the cost per gallon for the paint and the pine.
Hermann
4.6128 Answers
let cost of paint be x and cost of primer be y
4x + 9y = 275
3x + 5y = 180
muliply the 1st equation with -3 and the 2nd equation by 4
-12x - 27y = -825
12x + 20y = 720
add both equations
-7y = -105
y = 15
substitute to equation 1
4x + 9*15 = 275
4x = 275 - 135
4x = 140
x = 35
therefore cost per gallon of paint is 35 while cost per gallon of primer is 15.
Frequently asked questions (FAQs)
Math question: Find the fifth derivative of f(x) = 3x^4 - 2x^2 + 5x - 1.
+
Math question: "What is the smallest positive integer solution to the equation x^n + y^n = z^n, where n>2?"
+
Math question: Find the fourth derivative of f(x) = cos(x^2) at x = π/2.
+
New questions in Mathematics