I bought 5 pens, 7 pencils and 4 erasers. Rajan bought 6 pens, 8 erasers and 14 pencils for an amount which was half more than what I had paid. The percentage of total amount spent on pens by me is :

Explanation

Let the price of a pen in rupees ` = x`

Let the price of a pencil in rupees `= y`

Let the price of an eraser in rupees `= z`

Let total money spent by me in rupees `= A`

Then, the total money spent by Rajan in rupees `= 3/2A`

With the given details,

`5x+7y +4z = A->(1)`

`6x+14y+8z = 3/2A->(2)`

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