Question

The price of petrol goes up by 20%. By how much per cent must Ajay reduce his consumption of petrol so that the expenditure on petrol remains the same?​

Answer 1

Answer:

let the price of 1 litre petrol be 100 rupees..

Then, 20% of 100 = 20/100 * 100 = 20 rupees

Ajay reduce his consumption = 100- 20 = 80 rupees...

Mark me as brainliest please

Answer 2

SOLUTION -

⟹ Let the consumption of petrol originally be x L

⟹ and let it's cost be ₹ 100

⟹ New cost of x L of petrol = ₹ 120

⟹ Now, ₹ 120 can fetch x L of petrol

★ ₹ 100 can fetch $\dfrac{x}{120} \times 100$ L of petrol = $\dfrac{5x}{6}$ L of petrol

★ Reduction in consumption =

$(x - \dfrac{5x}{6} )$ L of petrol

= $\dfrac{x}{6}$ L of petrol

Reduction per cent in consumption

$= \dfrac{Reduction\:in\:consumption}{original\:consumption} \times 100\%$

$= \dfrac{ \frac{x}{6} }{x} \times 100\%$

$= \dfrac{50}{3} \%$

$= 16 \times \dfrac{2}{3} \%$

Hence, Ajay must reduce the consumption by $16 \times \dfrac{2}{3} \%$