Question

the rate of price of petrol is increased from rs 80 per litre to rs 88 per litre. find the percent increase in the price.

ans 10%

Answer 1

Answer:

Original price = Rs 80 .

Increased price = Rs 88 .

Find the increase in price

Increase in price = Increased price - original price

⇒ Increase in price = Rs 88 - Rs 80

⇒ Increase in price = Rs 8

Find the percentage

$\mathtt{Percentage=\frac{Increase\:in\:price}{Original\:price} \times 100}$

$\implies \frac{8}{80}\times 100\\\\\implies \frac{1}{10} \times 100\\\\\implies \frac{100}{10}\\\\\implies 10$

The percentage is 10 % .

Step-by-step explanation:

Whenever we are asked to find the percentage increase in something , we must find the increase in that thing .

Then we will divide the found value with the original price .

Then multiply the whole thing by 100 and we are done .

The word percentage means to divide the given value by 100 .

Hence we must multiply by 100 to find the % increase .

Answer 2

Answer:

10 %

Step By Step Explanation:

Given:

The initial rate of price = Rs 80 per litre.

The new rate of price = Rs 88 per litre.

∴ Increment in the rate of price is :

⇒ Rs 88 - Rs 80

⇒ Rs 8

Now, Increment in Percent is :

$\mathsf{ \blue{\implies \: \frac{Increment \: price}{Initial \: price} \times 100 \%}}$

$\mathsf{ \pink{\implies \: \frac{Rs\: 8}{Rs \: 80} \times 100 \%}}$

$\mathsf{ \pink{\implies \: 10 \: \%}}$

Hence, the rate of price of petrol is increased by 10 %.

Note: Percent of deducted price :

$\boxed {\boxed{ \mathsf{\implies \: \frac{Deducted \: price}{Initial \: price} \times 100 \%}}}$