cost of 2 pens and 5 books is ₹225 and 4 pens and 3 books is ₹320 then find cost of 1 pen
Answers
Answer :
cost of 1 pen = ₹66
Step-by-step explanation :
Given,
- cost of 2 pens and 5 books is ₹225
- cost of 4 pens and 3 books is ₹320
To find,
- cost of 1 pen
Solution,
Let the cost of 1 pen be ₹x and cost of 1 book be ₹y
According to the condition - 1,
⇒ cost of 2 pens = ₹2x
⇒ cost of 5 books = ₹5y
cost of 2 pens + cost of 5 books = ₹225
2x + 5y = ₹225 ---[1]
According to the condition - 2,
⇒ cost of 4 pens = ₹4x
⇒ cost of 3 books = ₹3y
cost of 4 pens + cost of 3 books = ₹320
4x + 3y = ₹320 ---[2]
Multiply equation [1] with 2,
2(2x + 5y) = 2(₹225)
4x + 10y = ₹450 ---[3]
Subtract equation [2] from [3],
4x + 10y - (4x + 3y) = 450 - 320
4x + 10y - 4x - 3y = 130
7y = 130
y = 130/7
2x + 5y = 225
2x + 5(130/7) = 225
2x + 650/7 = 225
2x = 225 - 650/7
2x = (1575 - 650)/7
2x = 925/7
x = 925/14
x = ₹66 (approx.)
The cost of 1 pen is approximately ₹66