Solution 1
In the question, it is given that if 1% of work is done on day 1, then on day 2 it would be 2% and in the following days, it will increase by 4%, 8%, 16% and so on.
Now we are already provided that the total work gets completed in 15 days. So we can easily figure out that if 100% of work is done on the 15th day, then on the 14th day only 50% of work is done. Similarly, we can arrive at our answer that on the 13th day 25% of the work is done.
Solution 2
Let the work done in first day be x and second day be 2x etc.
Day - Work done on the day | Total work done
1 - x x
2 - 2x 3x
3 - 4x 7x
4 - 8x 15x
5 - 16x 31x
6 - 32x 63 x
7 - 64x 127x
8 - 128x 255x
9 - 256x 511x
10 - 512x 1023x
11 - 1024x 2047x
12 - 2048x 4095x
13 - 4096x 8191x
14 - 8192x 16383x
15 - 16384x 32767x
32767x amount of work is done in 15 days. 25% of the work is 32767/4 = 8191.75x. 8191.75x of the work is completed in 13 days.
Check out this problem - 8 Queens Problem
Frequently Asked Questions
What is lateral thinking?
Lateral thinking is a technique of solving problems by logical reasoning and creative ideas.
A race track has five lanes. You are to find the 3 fastest horses out of a total of 25. How many races would have to be conducted to find the three fastest horses?
First, we have to conduct 5 races taking 5 horses each, then we need to convert another 1 race for all winners. This race decides the top 3 horses.
What do you understand by analytical skills?
It refers to the ability of thinking and working with data, figuring out patterns and drawing conclusions.
Conclusion
This article taught us how to solve the spider’s web puzzle.
We hope you could easily take away all critical and conceptual techniques by walking over the given examples.
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