Q5 of 23 Page 1

Attempt any two of the following sub questions:

Babubhai borrows Rs. 4,000 and agrees to repay with a total interest of Rs. 500 in 10 installments, each installment being less than the preceding installment by Rs. 10. What should be the first and last installments?

The given situation is in A.P where n = 10, S10 = 4500 and common difference = - 10

We know that



⇒ 4500 = 5[2a - 90]


⇒ 2a – 90 = 900


⇒ 2a = 990


⇒ a = 495


Also, an = a + (n - 1) × d where an is the nth term of A.P.


⇒ a10 = 495 + (10 - 1) × (- 10)


⇒ a10 = 495 - 90


⇒ a10 = 405


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4

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and , find the quadratic equation whose roots are and .

 5

Attempt any two of the following sub questions:

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Attempt any two of the following sub questions:

Given below is the frequency distribution of driving speeds (in km/hour) of the vehicles of 400 college students:



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