If 7 spiders make 7 webs in 7 days, then 1 spider will make 1 web ?
A. 1
B. 7/2
C. 7
D. 49
Answer : C. 7
Explanation:
Let the required number days be x.
Less spiders, More days (Indirect Proportion)
Less webs, Less days (Direct Proportion)
Hence we can write as,

-
- 1 x 7 x x = 7 x 1 x 7
- x = 7.