In a certain supermarket, a triangular display of cans is arranged in 10 rows, numbered 1 through 10 from top to bottom. Each successively numbered row contains 3 more cans than the row immediately above it. If there are fewer than 150 cans in the entire display, how many cans are in the sixth row?	Answers:	A) 14	B) 16	C) 18	D) 20	E) 22
Let x be the number of cans in row 1.   The total number of cans is x + (x+3) + ... + (x+27) =   10x + 3(1+2+...+9) =   10x + 3(9)(10)/2 =   10x + 135   Since the total is less than 150, x must equal 1.   The number of cans in the 6th row is 1 + 3(5) = 16   The answer is 16.
<result>B</result>
In a certain supermarket, a triangular display of cans is arranged in 10 rows, numbered 1 through 10 from top to bottom. Each successively numbered row contains 3 more cans than the row immediately above it. If there are fewer than 150 cans in the entire display, how many cans are in the sixth row?