Question

A store sells bread and milk. On Tuesday, 3 loaves of bread and 2 litres of milk were sold for €6.25. On Thursday

Answer 1

Equation is 4b + 5m = €10.90, and values of b and m are €1.35 and €1.1 respectively.

Step-by-step explanation:

• Step 1: Find equation for Thursday's sales.

Given b = price of a loaf of bread and m = price of one liter of milk

Total sales = €10.90

Equation ⇒ 4b + 5m = €10.90

• Step 2: Find the values of b and m.

3b + 2m = 6.25 ----- (1)

4b + 5m = 10.90 ---- (2)

Multiply eq(1) by 5 and eq(2) by 2 to make coefficients of m equal.

15b + 10m = 31.25

8b + 10m = 21.8

Subtract eq(2) from eq(1)

⇒ 7b = 9.45

⇒ b = 9.45/7 = €1.35

Substitute for b and find m using eq(1).

⇒ 3 × 1.35 + 2m = 6.25

⇒ 4.05 + 2m = 6.25

⇒ 2m = 2.2

∴∴ m = 2.2/2 = €1.1