The fourteen digits of a credit card are to be written in the boxes shown above. If the sum of every three consecutive digits is 18, then the value of x is :  Choose the correct choice: A) 1 B) 3 C) 8 D) 7 E) 9
Sol : A   Explanation:   Let us assume right most two squares are a , b   Then Sum of all the squares = 18 x 4 + a + b .......... (1)   Also Sum of the squares before 7 = 18   Sum of the squares between 7, x = 18   and sum of the squares between x , 8 = 18   So Sum of the 14 squares = 18 + 7 + 18 + x + 18 + 8 + a + b (2)   Equating 1 and 2 we get x = 3   Answer:3
<result>B</result>
The fourteen digits of a credit card are to be written in the boxes shown above. If the sum of every three consecutive digits is 18, then the value of x is :