## 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 spiderâ€™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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