RD Sharma

12. The car hire charges in a city comprise of a fixed charges together with the charge for the distance covered. For a journey of 12 km, the charge paid is ₹ 89 and for a journey of 20 km, the charge paid is ₹ 145. What will a person have to pay for travelling a distance of 30 km?

Solution: Let the fixed charge of the car be ₹ x and, Let the variable charges of the car be ₹ y per km. So according to the question, we get \[2\] equations \[x\text{ }+\text{ }12y\text{ }=\text{...

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10. Yash scored 40 marks in a test, getting 3 marks for each right answer and losing 1 mark for each wrong answer. Had 4 marks been awarded for each correct answer and 2 marks been deducted for each incorrect answer, then Yash would have scored 50 marks. How many questions were there in the test?

Solution: Let the total number of correct answers be x and the total number of incorrect answers be y. Their sum will give the total number of questions in the test = x + y According to the question...

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5. A and B each has some money. If A gives ₹ 30 to B, then B will have twice the money left with A. But, if B gives ₹ 10 to A, then A will have thrice as much as is left with B. How much money does each have?

Solution: Let he money with A be ₹ x and the money with B be ₹ y. According to the question, Case 1: If A gives ₹ \[30\]to B, then B will have twice the money left with A. Equation, \[y\text{...

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3. In a rectangle, if the length is increased by 3 metres and breadth is decreased by 4 metres, the area of the triangle is reduced by 67 square metres. If length is reduced by 1 metre and breadth is increased by 4 metres, the area is increased by 89 sq. metres. Find the dimension of the rectangle.

Solution: Let the length and breadth of the rectangle be x units and y units. The area of rectangle = xy sq.units Length is increased by 3 m ⇒ The new length is \[x+3\] Breadth is reduced by 4 m...

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2. The area of a rectangle remains the same if the length is increased by 7 metres and the breadth is decreased by 3 metres. The area remains unaffected if the length is decreased by 7 metres and the breadth is increased by 5 metres. Find the dimensions of the rectangle.

Solution: Let the length and breadth of the rectangle be x units and y units respectively. Hence, the area of rectangle = xy sq.units Length is increased by 7 m  ⇒ now, the new length is...

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If in a rectangle, the length is increased and breadth reduced each by 2 units, the area is reduced by 28 square units. If, however the length is reduced by 1unit and the breadth increased by 2units, the area increases by 33square units. Find the area of the rectangle.

Solution: Let the length and breadth of the rectangle be x units and y units respectively. The area of rectangle = xy sq.units Case 1: Length is increased by 2 units ⇒ The new length is \[x+2\]units...

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