Question
A car covers a distance of 60 km at a consistent speed.
If the car's speed is increased by 8 km/h, it would take 2 hours less to travel the same distance. What was the car's original speed?Solution
Let the actual speed of the car be 'x' km/h ATQ: Or, 60/x - 60/(x + 8) = 2 Or, 2x2 + 16x = 480 Or, x2 + 8x - 240 = 0 Or, x2 + 20x - 12x - 240 = 0 Or, x(x + 20) - 12(x + 20) = 0 Or, (x + 20)(x - 12) = 0 So, x = - 20, and x = 12 As speed cannot be negative So, x = 12 Original speed of the car is 12 km/hÂ
Individuals A and B have their incomes in the ratio of 5 to 3, while the ratio of their expenditures stands at 3 to 4, respectively. A saves Rs. 43,000 ...
In a department 20% of the employees are females. 40% of the male employees know Hindi. The total number of employees who know Hindi is 46%. Find the pe...
In a school, 60% of the students pass and 30 fail. The number of students appearing from another school is 25 more and 20 more students pass than the fo...
40% students (boys + girls) in a science class are boys. Out of total boys, 60% are literate and 120 are illiterate. Find the number of literate girls i...
A teacher distributes 300 toffees among her 4 students, A, B, C and D. A gets x% of total toffees, B receives 2x% of the remaining toffees, C receives (...
The current population of a city is 50,000. If the population of males increases by 4% and the population of females increases by 6%, the total populati...
A quantity is increased by 60% at first, and later decreased by 45%. Calculate the net percentage change.
'P' allocates 25% of his income to rent and then spends 40% of the remaining amount on food and travel. After these expenses, he spends Rs. 5600 on misc...
Akshay, Vishal and Dipak purchased 2, 20 and 50 notebooks for a total of Rs 16, Rs 140 and Rs 400 respectively from a stationery shop. In his transactio...
In a colony, there are 20 APL families and 30 BPL families. Each APL and BPL family got blankets equal to 30% and 60%, respectively of total number of f...
Relevant for Exams:
