Answer:
Orange juice costs 0.90, bagel costs 2 and a cup of coffee costs 0.45.
Step-by-step explanation:
Let x, y and z be the cost of the orange juice, the raisin bagel and the cup of coffee respectively,
Thus, the original cost = x + y + z
∵ the orange juice will cost twice as much as coffee
⇒ x = 2z ...........(1)
So, the total cost = 2z + y + z = y + 3z,
After increasing the price of orange juice by 50% and the price of bagels by 20%,
New cost = 150% of x + 120% of y + z = 1.5x + 1.2y + z = 3z + 1.2y + z = 1.2y + 4z
According to the question,
y + 3z = 3.35 .............(2)
1.2y + 4z = 4.20 ...........(3)
Equation (3) - 1.2 × equation (2),
4z - 3.6z = 4.20 - 4.02
0.4z = 0.18
⇒ z = 0.45,
From equation (2),
y + 1.35 = 3.35
⇒ y = 2,
From equation (1),
x = 2(0.45) = 0.9
