Question

Tea costs $x a packets and coffee $y a packet. Five packets of tea and seven of coffee cost $39.40 while three packets of tea and five of coffee cost $26.20. Work out the cost of a packet of tea

Answer 1

$4.53

Explanation:

Let us represent

The cost of a

Packet of tea = x

Packet of coffee = y

Five packets of tea and seven of coffee cost $39.40

5x + 7y = 39.40.....Equation 1

Three packets of tea and five of coffee cost $26.20.

3x + 5y = 26.20.......Equation 2

Combining both Equations

5x + 7y = 39.40.....Equation 1

3x + 5y = 26.20.......Equation 2

Multiply Equation 1 by 5 and Equation 2 by 7 to eliminate y

25x + 35y = 197.... Equation 3

21x + 35y = 183.4......Equation 4

Subtract Equation 4 from 3

3x = 13.6

x = 13.6/3

x = $4.53

Therefore, the cost of a packet of tea is $4.53