24*4= x(x+4)
solve this
answer is x=8
X+4= 12
4.224 days
4) QEOKTWG
If the bell rung when they r started is also counted then it
will be 5 otherwise 4
2hr 24min
Let the age of the man be x
Then age of his son becomes (x−24)
2 years later from now,
Age of man will be = x+2
and age of his son will be =(x−24+2)=x−22
According to question,
2(x−22)=x+2
i.e., 2x−44=x+2
i.e., x=46
Therefore ,
Present age of man=46 years
And present age of his son =46−24=22 years
There are 18 numbers between 100 and 300 that are divisible by 11: 110, 121, 132, 143, 154, 165, 176, 187, 198, 209, 220, 231, 242, 253, 264, 275, 286, 297.
Out of 10 persons, 4 are graduates; so, (10 – 4) = 6 are under-graduates.
If there is no restriction, any three can be chosen from the ten in (10C3) = 120 ways.
Now, if all three chosen are under-graduates; it can take place in (6C3) = 20 ways.
Therefore, the probability that there will be no graduate among the three chosen = (20 / 120) = (1 / 6).
Therefore, the probability that there will be at least one graduate among the three chosen = {1 – (1 / 6)} = (5 / 6) = 0.8333.
4%
(x**2 – 6* x + 5) = (x-1)*(x-5)
(x**2 + 2 * x + 1) = (x + 1) * (x+1) = (x+1)**2
For what x is (x-1)*(x-5)/( (x+1)**2) a minimum?
One way to answer this question is by using calculus.
Take the derivative, and set to zero.
Since this is a fraction of polynomials, and a fraction is
zero only if it’s numerator is zero, we need calculate only
the numerator of the derivative and set it to zero.
The numerator of the
Derivative of (x-1)*(x-5)/( (x+1)**2) is
( (x-1) + (x-5) ) ( x+1)**2 – (x-1)(x-5)( 2 (x+1) )
= (2 x – 6) (x+1)**2 – (2) (x-1)(x-5) (x+1)
= 0
Divide through by 2 (x+1)
(x-3)(x+1) – (x-1)(x-5) = 0
(x**2 – 2 x – 3 ) – (x**2 – 6 x + 5) = 0
x**2 – x**2 – 2 x + 6 x – 3 – 5 = 0
4 x – 8 = 0
x = 2
Plugging in x = 2 into the original
(x**2-6*x+5)/(x**2+2*x+1)
gives us (2**2 – 6 * 2 + 5)/(2**2 + 2*2 + 1)
= (4 – 12 + 5) / (4 + 4 + 1) = -3/9 = -1/3
Least value is -1/3
38 / 2 = 19 – 5 = 14 years old
b
I will try to find that person
Or give that bag to police ..
Speed of train = 54km/hr
= 54 x (5/18) m/s
= 15 m/s
Length of train = 165m
Time required to cross a bridge of 660m in length = (660+165) / 15
= 55 seconds
A. 80 : 81 : 84
2.5 sec