- If 7 spiders make 7 webs in 7 days.
- Days required by one spider to make one web will be figure out in this way.
Explanation
Three given entities here are
- Spiders
- Web
- Days
To determine the relation here, let suppose; Days required by one spider to make one web = y
Case I
Spiders Days
7 7
1 y
- Seven spiders requires less days.
- One spider will require more days.
This clearly indicates that there is inverse relation.
Direct/Indirect relation tells how the equation will be written.
1 : 7 :: 7 : y ________ (i)
Case II
Web Days
7 7
1 y
- 7 (seven) web requires more days.
- 1 (one) web would require less days.
This clearly indicates that there is direct relation.
Direct/Indirect relation tells how the equation will be written.
7 : 1 :: 7 : y ________ (ii)
By (i) and (ii)
1 : 7 :: 7 : y
7 : 1
7 x 1 x 7 = 7 x 1 x y ________ (A)
After simplifying equation (A), we can easily figure out the value of y (y = 7)
To Find
Days required by one spider to make one web = ?
Solution
Method I
Let suppose
Days required by one spider to make one web = y
Spider Web Days
7 7 7
1 1 y
- Relation between spider and days is inverse.
- Relation between web and days is direct so;
1 : 7 :: 7 : y
7 : 1
7 x 1 x 7 = 7 x 1 x y
49 x 1 = 7y
7y = 49
y = 49/7
y = 7 days
Days required by one spider to make one web = 7 days answer
Method II
Days required by 7 spiders to make 7 web = 7 days
Days required by 7 spiders to make 1 web = 7/7 days
Days required by 7 spiders to make 1 web = 1 day
Days required by 1 spider to make 1 web = 1 x 7 days
Days required by 1 spider to make 1 web = 7 days
Days required by one spider to make one web = 7 days answer
Conclusion
If 7 spiders make 7 webs in 7 days then one spider will make one web in 7 days.
