Question

1)
Iraa wants to buy a car. She want to select a car depends on usage of petrol by it. Car A travels x km for
every litre of petrol, while car B travels (x + 5) km for every litre of petrol.
Help her to choose perfect car for her by finding litres of petrol used by car A and car B in covering a
distance of 400km. If car A uses 4 litres of petrol more than car B in covering 400 km, write down an
equation, in x and solve it to determine the number of litres of petrol by car B for the journey.​

Answer 1

If Car A travels x km for 1 litre of petrol and car B travels (x+5) km for 1 litre, then-

Let x = 20 km, so that (x+5) = 20+5 = 25 km

Litres of petrol used by car A in covering 400 km

$= \frac{400}{20}litres$

$= 20 \: litres$

and Litres of petrol used by car B in covering 400 km

$= \frac{400}{25} litres$

$= 16 \: litres$

Here petrol used by Car A is 4 more than Car B

The equation becomes:-

(No. of litres + 4) × 20 = 400

(No. of litres + 4) = 400 ÷ 20

No. of litres + 4 = 20

No. of litres = 20 - 4

No. of litres = 16 litres

So, petrol used by car B is 16 litres

So, she should bye car B, as it will travel same distance as car A in less litres of petrol than Car A.

Answer 2

Answer:

B

Step-by-step explanation:

If Car A travels x km for 1 litre of petrol and car B travels (x+5) km for 1 litre, then-

Let x = 20 km, so that (x+5) = 20+5 = 25 km

Litres of petrol used by car A in covering 400 km

and Litres of petrol used by car B in covering 400 km

Here petrol used by Car A is 4 more than Car B

The equation becomes:-

(No. of litres + 4) × 20 = 400

(No. of litres + 4) = 400 ÷ 20

No. of litres + 4 = 20

No. of litres = 20 - 4

No. of litres = 16 litres

So, petrol used by car B is 16 litres

So, she should bye car B, as it will travel the same distance as car A in fewer litres of petrol than Car A.