The ratio of the speed of boat ‘A’ in still water, the speed of boat ‘B’ in still water and the speed of the current is 7:4:2, respectively. If the time taken by boat ‘A’ to travel (7D – 20) km downstream is equal to the time taken by boat ‘B’ to travel (D + 65) km upstream, then find the value of ‘D’.
Let, the speeds of boat ‘A’ and boat ‘B’, in still water and the speed of the current be 7x km/hr, 4x km/hr and 2x km/hr, respectively. According to the question, (7D – 20)/(7x + 2x) = (D + 65)/(4x – 2x) Or, 14D – 40 = 9D + 585 Or, 5D = 625 Or, D = 125
I. 27x² + 120x + 77 = 0
II. 56y² + 117y + 36 = 0
How many values of x and y satisfy the equation 2x + 4y = 8 & 3x + 6y = 10.
I. 96x² + 52x - 63 = 0
II. 77y² + 155y + 72 = 0
I. 2x² + 15 x - 27 = 0
II. 3 y² + 25 y - 18 = 0
I. 2x2 + 5x + 2 = 0
II. 4y2 = 1
I. 6x² - 23x + 7 = 0
II. 6y² - 29y + 9 = 0
I. 9/(4 )p + 7/8p = 21/12
II. 7/5p = 9/10q + 1/4
I. 2y2+ 13y + 15 = 0
II. 2x2+ 11 x + 12 = 0
I. 7x² + 27x + 18 = 0
II. 19y² - 27y + 8 = 0
I. 6y2- 17y + 12 = 0
II. 15x2- 38x + 24 = 0
