A. 7.5m
B. 8.5m
C. 10.5m
D. 12.5m
A. If x < y
B. If x > y
C. If x ≤ y
D. If x = y or the relationship between x and y cannot be established.
Explanation:
I. x2 + 3x + 2x + 6 = 0
=> (x + 3)(x + 2) = 0 => x = -3 or -2
II. y2 + 7y + 2y + 14 = 0
=> (y + 7)(y + 2) = 0 => y = -7 or -2
No relationship can be established between x and y.
A. 16 2/3%
B. 30%
C. 33 1/3%
D. 33 1/6%
A. 46
B. 32
C. 68
D. 51
Explanation:
Sum of all the 13 numbers = 13 * 60 = 780
Sum of the first 7 of them = 7 * 57 = 399
Sum of the last 7 of them = 7 * 61 = 427
So, the 8th number = 427 + 399 – 780 = 46
A. 39 seconds
B. 40 seconds
C. 39.38 seconds
D. 39.5 seconds
The first pole is crossed at the zeroth second. The timer starts after the car crosses the first pole. Let the distance between each pole be x m. To reach the 16th pole, the distance travelled by the car is 15x. The speed of the car is 15x/30 = x/2 m/s To reach the 21st pole, it has to travel a distance of 20x. Time taken
= 20x÷(x/2)
= 40 seconds
A. 19
B. 20
C. 21
D. 22
let her age be x
after 1 year her age will be x+1=2(x-10)
x+1=2x-20
1+20=2x-x
x=21 years