GATE Questions

---

Light year is the unit of to express astronomical distances, that light can travel in one year. Light moves at a velocity of about 300,000 kilometers (km) each second. So in one year, it can travel about 10 trillion km. More precisely, one light-year is equal to 9,500,000,000,000 kilometers.

Approximately, 1 light year = 10^16 mts.

The numbers 0,1,2,3,4,5,6,7,8,9 are 10 in number while preparing telephone numbers any number can be used any number of times.

This can be done in 105ways, but '0' is there

So, the numbers starting with '0' are to be excluded is 94 numbers.

 Total 5 digit telephone numbers = 105- 94 = 3439

At least one black can be chosen in two ways from each box:
Now, probability of choosing at least one black ball from first box 

= 1/2 × [ (2C1× 2C1)/4C2 + 2C2/ 4C2 ]= 5/12

Probability of choosing at least one black ball from 2nd box
= 1/2 × [(4C1×12C1)/16C2 + 4C2/ 16C2] = 9/40

Final probability

= 5/12 + 9/40 = (50 + 27)/120 = 77/120

The main use of salt in the diet is to produce in small amounts the hydrochloric acid required for the digestion of food.

Ans. 
Let B’s investment = x rs.
∴ A’s investment =( x + 1200) rs.
Ratio of the profits of A and B = (x+1200)*(15+4):x*15 = {19(x+1200)}:15x
Now,let the total profit of A =y
∴ total profit of B = (y-280)
But total profit = 1240
⇒y+(y-280)=1240
⇒2y=1520
⇒y= 760
∴profit of A = 760rs.
Profit of B = 760-280=480 rs.
Ratio of profits= 760:480 = 19:12
According to the question,

19(x+1200)/15x = 19/12

12x+14400 = 15x

⇒3x = 14400
⇒x = 4800 rs.
⇒investment of A = 4800+1200
                          = 6000 rs.

Sum of all numbers in each row and columns must be 15.

In last row to gt sum as 15 missing number must replaced by 1. 

K's 1 day's salary = 1/10
L's 1 day's salary = 1/15
Together their 1 day's salary = 1/10 + 1/15
= 3/30 + 2/30
= 5/30
= 1/6
So the money will be enough for paying them both for 6 days.

IEEE 1284 is a standard that govern parallel communications.

• IEEE 1284 is a standard that defines bi-directional parallel communications between computers and other devices.

• It was originally developed in the 1970s by Centronics, and was widely known as the Centronics port, both before and after its IEEE standardization.