Let 'A' be the cost price of property P1.

Then from the given data, the selling price of P1 = Rs. 1,00,000

He got 20% loss on selling P1

$$\begin{gathered} ? A - 20 A 100 = 100000 \\ ? A = 1 , 25 , 000 \end{gathered}$$

Therefore, the amount he lossed on selling P1 = 25,000

As ge he got no loss or gain on sale of P1 and P2, the gain on selling P2 = 25,000

But the selling price of P2 = 1,00,000 => Cost price of P2 = 75,000

Hence, the profit percentage on P2 =  Gain CP x 100 = 25000 75000 x 100 = 100 3 = 33 . 33 %

Let 'x' be the cost price.
Now Marked price = x + 30x/100 = 13x/10
10% discount = 10/100 x 13x/10 = 13x/100
Selling price = 13x/10 - 13x/100 = 117x/100
Given gain = 340
Here gain = 117x/100 - x = 17x/100 = 340 => x = Rs. 2000.

According to the given data,

Let Cost price of the article be 'cp'

Then,

102.25 cp - 92 cp = 164 x 100

10.25 cp = 16400

cp = 1600

Now, if he sells at Rs. 1760

Profit = 1760 - 1600 = 160

Profit% = 160/1600 x 100 = 10%.

least cost price      = 200*8 = 1600
greatest sold price = 425 * 8 = 3400
profit required = 3400- 1600 = 1800

Let the cost price be Rs. 100
Then, market price is Rs. 140
Now, the first discount is of 28.57% Rs.140 =~ Rs. 40
Hence, its selling price = 140 - 40 = Rs. 100
Now since Rana is selling at cost price, any further discount will be equal to loss percentage.
The next dicount of 12.5% will be the loss percentage to Rana.

As given in the question, Marked price is 25% more than the Cost price.

=> C.P of the article =  3 4 x 400 = 300

Now, 

Let the original S.P of the article be Rs. P

Now the new S.P = P +  16 . 666 + 13 . 333 300 x P

=> S.P =  7 P 6

According to the question,

7 P 6 - 300 = 2 P - 300

=> 5P = 1800

=> P = Rs. 360

Hence, the increased S.P = 360 x 7/6 = Rs. 420. 

Let CP = 100,
42 % increase => SP = 142
10 % discount in SP => ((142 x 10)/100) = 14.2
So 1st SP = (142 - 14.2) = 127.8, again 12 % discount in 1st SP ((127.8 x 11)/100) = 14.058
2nd SP = (127.8 - 14.058) = 113.742,
So finally CP = 100, SP = 113.742, => gain = 13.742%.

Let Cost Price(C.P) = P
gain% = {(S.P-C.P)/C.P} x 100
25 = {(1540-P)/P} x 100
25/100 = (1540-P)/P
=> P = 4(1540)-4P
=> 5P = 4(1540)
=> P = 1232
So, Cost Price = Rs. 1232

Let the marked price of the router be Rs. P

From the given data,

$$\begin{gathered} P x 85 100 - P x 80 100 = 51 \\ P x 5 100 = 51 \\ ? P = 5100 5 = 1020 \end{gathered}$$

Hence, the original marked price of the router is Rs. 1020.

Money invested by Rajan before 1 year was = Rs. 100000

Money in UK pounds @ 75 is = 100000/75 = 1333.33 Pounds

Now, after 1 year invested amount was appreciated by 20%

=> 20% of 1333.33 = 266.66

Total investment becomes = 1333.33 + 266.66 = 1600 Pounds

This 1600 Pounds @ Indian currency at 80 = 1600 x 80 = Rs. 1,28,000

Hence, Rajan's investment of Rs. 1,00,000 becomes Rs. 1,28,000 in 1 year

Therefore, his profit % = [(128000 - 100000)/100000] x 100 = 28%.