Question

If 30 lb of rice and 20 lb of potatoes cost ​$18.20​, and 20 lb of rice and 12 lb of potatoes cost ​$11.52​, how much will 10 lb of rice and 50 lb of potatoes​ cost? let x be the cost of 1 lb of rice and y be the cost of 1 lb of potatoes. set up two linear equations from the given information using x and y as the variables.

Answer 1

⇒let the cost of 1 Ib of rice be "x" and that of 1 ib of potatoes be "y"

30x + 20y = 18.20..........equation ( i )
20x + 12y =11.52...........equation ( ii )

⇒30x + 20y = 18.20.........×2
⇒20x + 12y = 11.52.........×3

60x + 40y = 36.40
60x + 36y = 34.56
↓
4y = 1.84
y = 0.46

value of x.
30x = 18.20 - 20(0.46)
30x = 9
x = 0.3

cost of 10 ib of rice and 50 ib of potatoes?
10x + 50y = ?
10(0.3) + 50(0.46) = 26

Answer = 26 Dollars