A. 26.4 m2
B. 39.6 m2
C. 52.8 m2
D. 79.2 m2
A. 2000
B. 3000
C. 4000
D. 6000
Explanation:
Let 815 + ? be k
=> 84k/100 – (815 * 84)/100 = 1680
=>84(k/100 – 815/100) = 1680
=> (k – 815)/100 = 20 => k = 2815
k = 815 + ? = 2815 => ? = 2000
A. 13, 3
B. 12, 6
C. 15, 3
D. 14, 4
Explanation:
Let the speed of the man in still water and speed of stream be x kmph and y kmph respectively.
Given x + y = 18 — (1)
and x – y = 10 — (2)
From (1) & (2) 2x = 28 => x = 14, y = 4.
A. Rs. 1550
B. Rs. 1650
C. Rs. 1750
D. Rs. 2000
A. 3 1/3 km/hr
B. 3 1/9 km/hr
C. 1 ¼ km/hr
D. 4 2/3 km/hr
Explanation:
Let Speed upstream = x km/hr
Speed downstream = 3x km/hr
Speed in still water = ½ (x+3x) km/hr = 2x km/hr
Speed of current = ½ (3x-x) km/hr = x km/hr
2x = 28/3 or x = 14/3 = 4 2/3 km/hr
A. 3, -3/2
B. 3/2, -3
C. -3/2, -3
D. 3/2, 3
Explanation:
2×2 + 6x – 3x – 9 = 0
2x(x + 3) – 3(x + 3) = 0
(x + 3)(2x – 3) = 0
=> x = -3 or x = 3/2.