Question
If a sum when placed at compound interest grows to
Rs.6,400 in 2 yrs and to Rs. 8,000 in 3 yrs, find the rate percent p.a.Solution
Let the principal be P. ∴ P + CI for 3 yrs = Rs. 8,000----- (i) And P + CI for 2 yrs = Rs. 6,400----- (ii) Subtracting (ii) from (i), we get CI for the 3rd yr = 8,000 – 6,400 = Rs. 1600 Thus, CI calculated in the 3rd yr is basically the interest on the amount generated after 2 yrs which is Rs. 6,400. R = (SI × 100)/(P × T) = (1600 × 100)/(6400 × 1) = 25 % p.a.
I. x2 – 39x + 360 = 0
II. y2 – 36y + 315 = 0
I. 40 x² - 93 x + 54 = 0
II. 30 y² - 61 y + 30 = 0
What will be the product of smaller roots of both equations.
I. 3x2 - 14x + 15 = 0
II. 15y2 - 34 y + 15 = 0
I. x2 – 13x + 36 = 0
II. 3y2 – 29y + 18 = 0
Equation 1: 2x2 - 21x + 54 = 0
Equation 2: 4y2 - 23y + 15 = 0
Difference between the roots of equation 1 is approx...
I. 4x² - 15x + 9 = 0
II. 20y² - 23y + 6 = 0
- For what value of a does the quadratic equation x² + ax + 81 = 0 have real and identical roots?
In each of these questions, two equations (I) and (II) are given.You have to solve both the equations and give answer
I. x² - 8x + 15 = 0 ...
I. 3x2 + 3x - 60 = 0
II. 2y2 - 7y + 5 = 0