Question
If a nine-digit number 89563x87y is divisible by 72,
then the value of √ (5x -4y) will be ∶Solution
Nine-digit number 89563x87y is divisible by 72, so the number is also divisible by 8 and 9. Divisibility law of 8 ⇒ A number divisible by 8 if its last three digits are divisible by 8. Divisibility law of 9 ⇒ A number is divisible by 9 if the sum of its digits is divisible by 9. 87y divisible by 8 if y = 2 Nine-digit number 89563x872 is divisible by 9 if the sum of its digits is divisible by 9. = 8+9+5+6+3+x+8+7+2 =48+x So, putting the value of x= 6 Now -√ (5x -4y) = √ (5×6 – 4×2) = √22.
At a round table, n persons are seated on n chairs. The probability that two friends from same college are sitting next to each other, is:
The deseasonalised time - series data will have only trend (T), cyclical (C) and irregular (I) components and is expressed as:
The grouped data for the observation are as follows.
Class : 2-4 4-6 6-8<...
These seventh decile (D7) of data set 4, 3, 10, 9, 1 is
The coefficient of correlation is the _________ of coefficients of regression.
Five persons A, B, C, D and E occupy seats in a row at random. The probability that A and B sit next to each other is:

Which option is WRONG?
Which option is incorrect for the component of ti.me series.
