We know that:
- Leonard can read 5 pages in 15 minutes
- Penny can read 15 pages in 1 hour
And we must find how much longer it would take Penny to read a 600-page book than Leonard.
To find it we can use two tables with the information and find the time will take Leonard and Penny read a 600 pages book using rule of 3
Rule of 3:
1. Leonard:
Then, using rule of 3
![x1=(15\cdot600)/(5)=1800](https://img.qammunity.org/2023/formulas/mathematics/high-school/h3avj9y2p1fpg9kpxlhxb9uv9jgio9koyb.png)
So, read a 600 page book will take Leonard 1800 minutes.
2. Penny:
![x2=(60\cdot600)/(15)=2400](https://img.qammunity.org/2023/formulas/mathematics/high-school/eev9dr211suy4unu0rk0cx68jkepg03bxg.png)
So, read a 600 page book will take Penny 2400 minutes.
So, the difference between Penny and Leonard would be
![2400minutes-1800minutes=600minutes](https://img.qammunity.org/2023/formulas/mathematics/high-school/aaug3by1k3kmb0j8s15q22aubvsoqo7loz.png)