Database Administration Questions

Speed of the boat upstream = 36/9 = 4 kmph

Speed of the boat in downstream = 36/6 = 6 kmph

Speed of stream = 6-4/2 = 1 kmph

In the question it is asked for 5% of 1500

5 x 1500/100 = 15 x 5 = 75.

Hence, 5% of 1,500 is equal to 75.

In order to use any object as Key in HashMap, it must implements equals and hashcode method in Java.

According to the given data,

Let Cost price of the article be 'cp'

Then,

102.25 cp - 92 cp = 164 x 100

10.25 cp = 16400

cp = 1600

Now, if he sells at Rs. 1760

Profit = 1760 - 1600 = 160

Profit% = 160/1600 x 100 = 10%.

Let the present ages be K,M

Given K/M = 4/5

5K - 4M = 0 ......(1)

Also given that,

M - (K + 5) = 3

M - K = 8 .........(2)

Then, by solving (1) & (2)

M = 40 yrs and K = 32 yrs

Hence, Total of ages = 40 + 32 = 72 yrs

Difference of ages = 40 - 32 = 8 yrs.

The letter 'E'.

As of the above given data,

It is in the 1st place in Earth, 2nd in Heaven and in the middle of the Sea.

It appears once in a Year and twice in a Week.

It is present in February, June, September, October, November & December.

But not in the Month.

Hence, it is the letter 'E'.

Given principal amount = Rs. 8000

Time = 3yrs

Rate = 5%

C.I for 3 yrs = $$\begin{gathered} 8000 x 105100 x 105100 x 105100 - 8000 \\ = Rs. 1261 \end{gathered}$$

Now, C.I for 2 yrs = $$\begin{gathered} 8000 x 105100 x 105100 \\ = Rs. 820 \end{gathered}$$

Hence, the required difference in C.I is 1261 - 820 = Rs. 441

Let that something be 'x'

From the given data,

x + x/5 = 21

5x + x/5 = 21

6x = 21 x 5

=> x = 17.5

Hence, that something is x = 17.5.