Question

A laptop was sold at a profit of 15%. If it was sold at
a price that was 10% lower, the profit would have
been Rs.1050. What is the cost price of the laptop?
(A) 321000
(B) 35000
(C) 230000
(D) 42000​

Answer 1

Answer:

• Cost Price of the laptop is ₹ 30000.

Step-by-step explanation:

Given that:

• A laptop was sold at a profit of 15%.
• If the laptop was sold at a price that was 10% lower, the profit would have been ₹ 1050.

To Find:

• Cost price of the laptop.

Let us assume:

• The cost price of the laptop be x.

Finding selling price at a profit of 15% :

$\rm{\longmapsto x+(15\%\;of\;x)}$

Solving the bracket,

$\rm{\longmapsto x+\bigg(\dfrac{15}{100}\times x\bigg)}$

$\rm{\longmapsto x+\bigg(\dfrac{15x}{100}\bigg)}$

Opening the bracket,

$\rm{\longmapsto x+\dfrac{15x}{100}}$

Adding the numbers,

$\rm{\longmapsto \dfrac{100x+15x}{100}}$

$\rm{\longmapsto \dfrac{115x}{100}}$

Reducing the numbers,

$\rm{\longmapsto \dfrac{23x}{20}}$

Finding selling price 10% lower than the profit of 15% :

$\rm{\longmapsto \dfrac{23x}{20}-\bigg(10\%\;of \;\dfrac{23x}{20}\bigg)}$

Solving the bracket,

$\rm{\longmapsto \dfrac{23x}{20}-\bigg(\dfrac{10}{100}\times\dfrac{23x}{20}\bigg)}$

Cutting off the zeros,

$\rm{\longmapsto \dfrac{23x}{20}-\bigg(\dfrac{1\!\!\!\not{0}}{100}\times\dfrac{23x}{2\!\!\!\not{0}}\bigg)}$

$\rm{\longmapsto \dfrac{23x}{20}-\bigg(\dfrac{1}{100}\times\dfrac{23x}{2}\bigg)}$

Multiplying the numbers,

$\rm{\longmapsto \dfrac{23x}{20}-\bigg(\dfrac{23x}{200}\bigg)}$

Opening the bracket,

$\rm{\longmapsto \dfrac{23x}{20}-\dfrac{23x}{200}}$

Subtracting the numbers,

$\rm{\longmapsto\dfrac{230x-23x}{200}}$

$\rm{\longmapsto \dfrac{207x}{200}}$

According to the question:

$\rm{\longmapsto \dfrac{207x}{200}-x=1050}$

Subtracting the numbers,

$\rm{\longmapsto \dfrac{207x-200x}{200}=1050}$

$\rm{\longmapsto \dfrac{7x}{200}=1050}$

Transposing 200 from LHS to RHS and changing its sign,

$\rm{\longmapsto 7x=1050\times200}$

Multiplying the numbers,

$\rm{\longmapsto 7x=210000}$

Transposing 7 from LHS to RHS and changing its sign,

$\rm{\longmapsto x=\dfrac{210000}{7}}$

Dividing the numbers,

$\rm{\longmapsto x=30000}$

Hence, cost price of the laptop is ₹ 30000.

Answer 2

Answer:

30000

Step-by-step explanation:

Let Consider

C.P.= 100

if profit is 15%

then S.P.=115

According to question if price lowered by 10%

then new S.P. =103.5 (10% of 115=11.5; 115-11.5)

So new profit = Rs 3.5  (S.P-C.P=>103.50-100=3.50)

But in question we have given real profit is 1050

So if 3.5=1050

1=300

and we consider C.P.=100

Real C.P.= 300×100=30,000