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Q. Is the following situation possible? If so, determine their present ages. The sum of the ages of two friends is 20 years. Four years ago, the product of their ages in years was 48. Ans:Â (note: In this question, we justify the answer with proper reason) Let’s consider the ages of friends as X years […]
NCERT book maths class 10th
Q. Is it possible to design a rectangular park of perimeter 80m and the area 400 m2? If so, find the length and breadth. Ans: Let’s consider the length of rectangular as X m and width as Y m. By given 1st condition, its perimeter is 80m By given 2nd condition, its area is 400
Q. Is it possible to design a rectangular mango grove whose length is twice its breadth, and the area is 800 m2? If so, find the length and breadth. Ans: Let’s consider the length of rectangular as X m and width as Y m. By given 1st condition, its length is twice its breadth… ∴
Q. Find the values of k for following quadratic equation, so that it has equal roots: kx (x -2) + 6 = 0 Ans:Â Given quadratic equation: kx (x – 2) + 6 = 0 by simplifying this we get kx2 – 2 kx + 6 = 0 Let’s compare the given equation with standard
Q. Find the values of k for following quadratic equation, so that it has equal roots: 2×2Â + kx + 3 = 0 Ans:Â Let’s compare the given equation with standard quadratic equation: Standard quadratic equation: a x2Â + bx + c = 0 Given quadratic equation: 2×2Â + kx + 3 = 0 By comparing these two
Q. Sum of the areas of two squares is 468 m2. If the difference of their perimeters is 24 m, find the sides of the two squares. Ans:Â Let consider the sides of the two squares be x m and y m. We know that the area of a square is given by: Hence, area
Q. An express train takes 1 hour less than a passenger train to travel 132 km between Mysore and Bangalore (without taking into consideration the time they stop at intermediate stations). If the average speed of the express train is 11 km/h more than that of the passenger train, find the average speed of the
Q. A train travels 360 km at a uniform speed. If the seed had been 5 km/h more, it would have taken 1 jour less for the same journey. Find the speed of the train. Ans:Â Let take the speed of the train be x km/h. We know that the time ‘T’ taken to cover
(Q) The difference of squares of two numbers is 180. The square of the smaller number is 8 times the larger number. Find the two numbers. Ans:Â Step 1: Make equations: Let the smaller number be x and larger number be y. By 1st condition, y2 – x2 = 180 …. (i) By 2nd condition,
(Q) Rohan’s mother is 26 years older than him. The product of their ages (in years) 3 years from now will be 360. We would like to find the Rohan’s present age. Ans: Let’s Rohan’s age be km /h Hence, his mother’s age is 3 years later, Rohan’s age will be: and his mother’s age