If 7 spiders make 7 webs in 7 days, then how many days are needed for 1 spider to make 1 web?	Choose the correct option:
A) 1  B) 7  C) 3  D) 14  E) 15
Explanation :   Let, 1 spider make 1 web in x days.   More spiders, Less days (Indirect proportion)   More webs, more days (Direct proportion)   ⇒ 7 × 1 × 7 = 1 × 7 × x   ⇒x=7. Answer : Option 7
<result>B</result>
If 7 spiders make 7 webs in 7 days, then how many days are needed for 1 spider to make 1 web?