Question

5) An article of cost price increare 20%. in 1st year and decrease by 20%. find the how% decrease are or increase of cost price of a​

Answer 1

Given :-

The cost price of an article is increased 20% on the first year and decreased in the second year.

To find :-

The increase or decrease percentage of the cost price of the article .

Solution :-

Let the cost price of an article be Rs. X

Increased percentage of the cost price in the first year = 20%

Increase in the cost price = 20% of X

= 20% × X

= (20/100)×X

= (1/5)×X

= (1×X)/5

= Rs. X/5

The cost price of the article after increased

= X+(X/5)

= (5X+X)/5

= Rs. 6X/5

Decreased percentage of the cost price in the second year = 20%

Decrease in the cost price = 20% of 6X/5

= 20% × (6X/5)

= (20/100)×(6X/5)

= (1/5)×(6X/5)

= (1×6X)/(5×5)

= Rs. 6X/25

The cost price of the article after decreased

= (6X/5)-(6X/25)

LCM of 5 and 25 = 25

= [(6X×5)-(6X)]/25

= (30X-6X)/25

= Rs. 24X/25

We have,

Original cost price of the article = Rs. X

New cost price of the article = Rs.24X/25

Original cost price > New cost price

Decrease in the cost price in the whole transaction = X-(24X/25)

= (25X-24X)/25

= Rs. X/25

Decrease percentage = [Decrease in the CP/Original CP]×100

= [(X/25)/X] × 100

= (X/25X)×100

= (1/25)×100

= 100/25

= 4

Answer :-

The decreased percentage of the Cost Price of the article is 4

Answer 2

Step-by-step explanation:

Given :-

The cost price of an article is increased 20% on the first year and decreased in the second year.

To find :-

The increase or decrease percentage of the cost price of the article .

Solution :-

Let the cost price of an article be Rs. X

Increased percentage of the cost price in the first year = 20%

Increase in the cost price = 20% of X

= 20% × X

= (20/100)×X

= (1/5)×X

= (1×X)/5

= Rs. X/5

The cost price of the article after increased

= X+(X/5)

= (5X+X)/5

= Rs. 6X/5

Decreased percentage of the cost price in the second year = 20%

Decrease in the cost price = 20% of 6X/5

= 20% × (6X/5)

= (20/100)×(6X/5)

= (1/5)×(6X/5)

= (1×6X)/(5×5)

= Rs. 6X/25

The cost price of the article after decreased

= (6X/5)-(6X/25)

LCM of 5 and 25 = 25

= [(6X×5)-(6X)]/25

= (30X-6X)/25

= Rs. 24X/25

We have,

Original cost price of the article = Rs. X

New cost price of the article = Rs.24X/25

Original cost price > New cost price

Decrease in the cost price in the whole transaction = X-(24X/25)

= (25X-24X)/25

= Rs. X/25

Decrease percentage = [Decrease in the CP/Original CP]×100

= [(X/25)/X] × 100

= (X/25X)×100

= (1/25)×100

= 100/25

= 4

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