- 4 notebooks and 3 packages of pens cost $7.43 and 5 notebooks and 2 packages of pens cost $7.03.
- Let the cost of 1 notebook be x and that of 1 package of pens be y.
- Therefore, cost of 4 notebooks = 4x, cost of 3 packages of pens = 3y.
- So, 4x + 3y = $7.43 ...(1)
- Also, cost of 5 notebooks = 5x, cost of 2 packages of pens = 2y.
- Therefore, 5x + 2y = $7.03 ...(2)
- Multiply equation (1) with 5, we get
5(4x + 3y) = $7.43 × 5
or, 20x + 15y = $37.15 ...(3)
- Multiply equation (2) with 4, we get
4(5x + 2y) = $7.03 × 4
or, 20x + 8y = $28.12 ...(4)
- Subtract (4) from (3), we have
20x + 15y-(20x + 8y) = $37.15 - $28.12
or, 7y = $9.03
or, y = $1.29
or, 4x + 3($1.29) = $7.43
or, 4x + $3.87 = $7.43
or, 4x = $7.43 - $3.87
or, 4x = $3.56
or, x = $0.89
Answer:
A) $0.89
Hope you could get an idea from here.
Doubt clarification - use comment section.