A man sells calculator at the rate of ? 250 each which includes a profit of 14%. What amount of profit while he earn in 19 days, if he sells 7 calculator per day?

Let CP = N
According to the question
(106N/100) - (104N/100) = 3
? 2N/100 = 3
? N = 300/2
= ? 150

Let CP = x
According to the question,
625 - x = x - 435
? 2x = 1060
? x = 1060/2 = ? 530

Let number of apples bought = 5 x 6 = 30 [LCM of 5 and 6]
CP = (10/5) x 30 = ? 60
SP = (15/6) x 30 = ? 75
? Gain = SP - CP = 75 - 60 = ? 15
? Gain % = (15/60) x 100 % = 25%

Let CP = 3x and SP = 7x
According to the question,
7x = 700
? x = 100
? CP = 3x = ? = 300

Here, a = 23, b = 20
? Required percentage profit = [(a - b)/b] x 100 %
= [(23 - 20)/20] x 100% = 15%

Here, 6 apples are gained over 18 apple.
? Gain percent = (6/18) x 100 %
= 33¹/₃%

CP = 405 / 0.9 = 450
New SP = Rs. 465
Profit (%) = [465-450 / 450] X 100 = 3.33%

Price after 10% discount = 10000 - 10 % of 10000 = 10000 - 0.1 x 10000 = 9000
Price after another 20% discount = 9000 - 20 % of 9000 = 7200
Price after 10% of transportation charges = 7200 + 7200 x 0.1 = 7920
Price after 10% of profit = 7920 + 7920 x 0.1 = 8712
? Selling price = 8712

Go through options. Consider option (b)
200 x 3.25 - 200 x 3 = Rs. 50 = ( 30+20 )
Hence option, (b) is correct


Alternatively: Rs. 0.25 is the difference on 1 banana
Rs. 1 is the difference on 1/0.25 = 4 bananas
Rs. 50 is the difference on 4 x 50 = 200 bananas

Profit (%) = goods lefts / goods sold X 100 = ( 50 / 450 ) X 100 = 11¹/₉ %

Alternatively : Suppose CP of 1g is Rs.1 then he sells goods worth Rs.450 only and charges Rs.500. So the profit is Rs.50 over the sale price of Rs. 450.