Advertisements
Advertisements
Question
Car A travels x km for every litre of petrol, while car B travels (x + 5) km for every litre of petrol.
If car A use 4 litre of petrol more than car B in covering the 400 km, write down and equation in x and solve it to determine the number of litre of petrol used by car B for the journey.
Advertisements
Solution
Given Distance = 400 km
Car A travels x km/litre.
Car B travels (x + 5) km/litre.
Car A uses 4 litre more than car B
∴ `(400)/x - (400)/(x + 5)` = 4
400 (x + 5) - 400x = 4x(x + 5)
400x + 2000 - 400x = 4x2 + 20x
4x2 + 20x - 200 = 0
4 (x2 + 5x - 500) = 0
x2 + 25x - 20x - 500 = 0
x (x + 25) - 20 (x + 25) = 0
(x + 25) (x - 20) = 0
∴ x = 20 - 25 ...(inadmissible)
No. of litre of petrol used by car B
= `(400)/(20 + 5)`
= `(800)/(25)`
= 16.
RELATED QUESTIONS
Find the roots of the following quadratic equation by factorisation:
`sqrt2 x^2 +7x+ 5sqrt2 = 0`
Solve the following quadratic equations by factorization:
`2/2^2-5/x+2=0`
Solve the following quadratic equations by factorization:
4x2 + 4bx - (a2 - b2) = 0
The difference of two numbers is 4. If the difference of their reciprocals is 4/21. Find the numbers.
Two pipes running together can fill a tank in `11 1/9` minutes. If one pipe takes 5 minutes more than the other to fill the tank separately, find the time in which each pipe would fill the tank separately.
Solve the following by reducing them to quadratic form:
`sqrt(y + 1) + sqrt(2y - 5) = 3, y ∈ "R".`
Find two consecutive integers such that the sum of their squares is 61
Find two consecutive odd integers such that the sum of their squares is 394.
A two digit number contains the bigger at ten’s place. The product of the digits is 27 and the difference between two digits is 6. Find the number.
In the centre of a rectangular lawn of dimensions 50 m × 40 m, a rectangular pond has to be constructed so that the area of the grass surrounding the pond would be 1184 m2 [see figure]. Find the length and breadth of the pond.
