The bill for five glasses of apple juice and four salads is $9.50, but the total for four glasses of apple juice and five salads is $10.30. What would the be the bill for a glass of juice and a salad?
Suppose one apple juice costs $x and salad costs $y we get 5x + 4y = 9.50 4x + 5y = 10.30 Multiplying equation (1) by 5 and (2) by 4 25x + 20y = 47.50 16x + 20y = 41.20
Subtracting we get - 9x = 6.30 x = 6.30/9 = .70 Putting value of x in (1) 5(.70) + 4y = 9.50 3.5 + 4y = 9.50 4y = 9.50 - 3.50 = 6.0 y = 6.00 / 4 = 1.50 Cost of 1 glass of apple juice is $0.70 and of 1 salad is $1.50 Therefore cost of bill for 1 glass of apple juice and 1 salad is .70+1.50 = $2.20