The number of `n` on negative integral solutions to the system of equations `a_1 + a_2 + a_3 + a_4 + a_5 = 25 and a_1 + a_2 + a_3 = 10` are

Let A be the set of 4-digit numbers a_1 a_2 a_3 a_4 where a_1 > a_2 > a_3 > a_4 , then n(A) is equal to

Let A be the set of 4-digit numbers a_1 a_2 a_3 a_4 where a_1 > a_2 > a_3 > a_4 , then n(A) is equal to

Let A be the set of 4-digit numbers a_1 a_2 a_3 a_4 where a_1 > a_2 > a_3 > a_4 , then n(A) is equal to

Let A be the set of 4-digit numbers a_1 a_2 a_3 a_4 where a_1 > a_2 > a_3 > a_4 , then n(A) is equal to

Consider the following statements : A number a_1 a_2 a_3 a_4 a_5 is divisible by 9 if 1. a_1 + a_2 + a_3 + a_4 + a_5 is divisible by 9. 2. a_1 - a_2 + a_3 - a_4 + a_5 is divisible by 9. Which of the above statements is/are correct?

Evaluate: /_\ |[1+a_1, a_2, a_3],[a_1, 1+a_2, a_3],[a_1, a_2, 1+a_3]|

Evaluate: /_\ |[1+a_1, a_2, a_3],[a_1, 1+a_2, a_3],[a_1, a_2, 1+a_3]|

Evaluate: /_\ |[1+a_1, a_2, a_3],[a_1, 1+a_2, a_3],[a_1, a_2, 1+a_3]|

For the A.P., a_1, a_2,a_3, ............., if a_4/a_7= 2/3 , find a_6/a_8 .

The average of a_1, a_2, a_3, a_4 is 16. Half of the sum of a_2, a_3, a_4 is 23. What is the value of a_1