If 7 spiders make 7 webs in 7 days, then 1 spider will make 1 web in how many days?
A
1
B
7/2
C
7
D
49
Correct Answer: 7
Let the required number days be x. Less spiders, More days (Indirect Proportion) Less webs, Less days (Direct Proportion) Spider 1 ; 7 Webs 7 : 1 ∴1×7×x = 7×1×7 ⇒x = 7