An article is sold for ₹6500 so as to earn a profit of 4%. A second article whose cost price is ₹3750,is sold at a loss of 4%. What is the overall gain or loss percent in the whole transaction?

selling price = 6500

Let cost price be 100. 

So. 

Profit of 1st article = $$\frac{4}{100}\times100$$

                                 =4

S.p = c .p + profit

6500 =100+4

         = 104

1 = 62.5

So.

100 = 6250

So profit = s.p - c.p

               = 6500-6250

                = 250

In 2nd article

consider selling price  100

Loss of 2nd article = $$\frac{4}{100}\times100$$

                                 = 4

So .

S.p+loss = c.p

100+4 = 104

Which is equal to 3750

104 = 3750

       = 36

Here 

100 s p = $$100\times 36$$ = 3600

So total c.p=3750+6250

                   = 10,000

 total s.p=3600+6500

                   = 10,100

    = $$\frac{10100-10000}{10000}\times 100$$

     =$$\frac{100}{10000}\times 100$$

  = 1%

Gain = 1%