model 1 profit x after discount y Section-Wise Topic Notes With Detailed Explanation And Example Questions

Answer: (d)

SP = $180 × 120/100$ = Rs.216

90% = 216

100% = $216/90 × 100$ = Rs.240

Answer: (d)

Present worth

= 1860 - 60 = Rs.1800

Time = ${100 × \text"True Discount"}/\text"Present worth × Rate"$

= ${100 × 60}/{1800 × 5} = 2/3$ year

= $(2/3 × 12)$ months = 8 months

Answer: (b)

C.P. of article = Rs.100

Marked price be x

${x × 88}/100$ = 121

$x = {121 × 100}/88$ = Rs.137.5

i.e. 37.5% above C.P.

Using Rule 9,

Here, r = 12%, R = 21%

Required percentage

= $({r + R}/{100 - r} × 100)$%

= $({12 + 21}/{100 - 12}) × 100%$

= $33/88 × 100%$

= $3/8 × 100$

= $300/8$% = 37.5%

Answer: (c)

Let the marked price = Rs.100

S.P = Rs.80

Profit = 25%

CP = Rs.$(100/125 × 80)$ = Rs.64

Profit after selling on marked price

= 100 - 64 = Rs.36

Gain % = $36/64 × 100$ = 56.25%

Using Rule 6,

Here, D = 20% r = 25%

Let, M.P. be Rs.100

$\text"MP"/\text"CP" = {100 + r}/{100 - D}$

$100/\text"CP" = {100 + 25}/{100 - 20}$

C.P. = ${100 × 80}/125$

C.P. = Rs.64

Profit = 100 - 64 = 36

Gain % = $36/64 × 100%$ = 56.25%

Answer: (d)

S.P. for a profit of 12%

= ${8000 × 112}/100$ = Rs.8960

Discount = 11200 - 8960 = Rs.2240

If the discount per cent be x, then

${11200 × x}/100 = 2240$

$x = {2240 × 100}/11200 = 20%$

Using Rule 6,

Here, M.P. = Rs.11200, C.P. = Rs.8000

r =12% D = x%

$\text"MP"/\text"CP" = {100 + r}/{100 - D}$

$11200/8000 = {100 + 12}/{100 - x}$

= $11200/8000 = 112/{100 - x}$

100 - x = 80 ⇒ x = 20%

Answer: (b)

Let C.P.of article = Rs.100

If the marked price of article be x, then

$x × 75/100$ = 120

$x = {120 × 100}/75$ = 160

i.e. 60% above the cost price

Using Rule 9,

r = 25%, R = 20%

Required percentage

= $({r + R}/{100 - r} × 100)$%

= $({25 + 20}/{100 - 25} × 100)$%

= $45/75 × 100$ = 60%