Question 1058380
 A clerk in a clothing department is arranging t-shirts in a display in stacks of equal size.
 When he separated the t-shirts into stacks of 4, there was one left over.
 When he tried stacks of 5, there was still one left over.
 The same was true for stacks of six.
 However, he was able to arrange the shirts evenly in stacks of 7. 
How many t-shirts were in the display that he was arranging?
:
The last statement tells us it has to be a multiple of 7 and because division
by 5 having a remainder of 1, the number will end in a 1 or a 6, 
A list of these numbers
21, 56, 91, 126, 141, 161, 196, 231, 266, 301, 336, 371

Divide these by 4 and 6, find a quotient with a remainder of 1. 
Only 301 shirts satisfies these requirements (in 43 stacks)