4 mat-weavers can weave 4 mats in 4 days. At the same rate, how many mats would be woven by 6 mat-weavers in 6 days?  Pick one:	A) 25	B) 9	C) 39	D) 61	E) 16

Rationale: "let the required number of bottles be x . more weavers , more mats ( direct proportion ) more days , more mats ( direct proportion ) wavers 4 : 6 : : 4 : x days 4 : 6 4 * 4 * x = 6 * 6 * 4 x = ( 6 * 6 * 4 ) / ( 4 x 4 ) x = 9 . answer is b ."
Answer: B