question:80 white and black tiles will be used to form a 10x10 square pattern. If there must be at least one black tile in every row and at least one white tile in every column, what is the maximum difference between the number of black and white tiles that can be used?
Options:
(A) 75
(B) 80
(C) 85
(D) 90
(E) 60
answer:(E)
Stream of consciousness:Answer = E
Please refer diagram below
70 - 10 = 60

question:Two workers can type two pages in two minuets then how many persons can type 18 pages in 6 minuets
Options:
(A) 2Workers
(B) 3Workers
(C) 6Workers
(D) 7Workers
(E) 8Workers
answer:(C)
Stream of consciousness:2Worker 2pages 2minutes
1Worker 1page 2minutes
1worker 18pages 36minutes
Therefore to reduce the time by 6 times, workers should be increased by 6 times

question:The simple interest on a sum of money is 4/9 of the principal and the number of years is equal to the rate percent. Find the rate and the time?
Options:
(A) 6 2/3%
(B) 6 2/8%
(C) 7 2/3%
(D) 6 5/3%
(E) 4 2/3%
answer:
(A)
Stream of consciousness:4/9 P = (P*R*R)/100
R = 20/3 = 6 2/3%