2.5%
[tex]if\ the\ art-rice\ of\ pen\ is\ x\\ so\ the\ toux\ is\ 8v-x\\ then\ (80-x)\bullet1\bullet1-a9\bulletx=28\\ so\ x=30.\\ So\ the\ selling\ price\ of\ box\ is\ RS.5\\ the\ selling\ price\ of\ pen\ is\ R527\\ R55+R_27=R8.2\\ so\ profit\ percent=\frac{R882-R830}{280-}\times100\ percent=2.5\ percent\\ (figure\ out\ their\ individual\ oosts)[/tex]
I hope this helps you
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