Question 15
To fill with water a tank in the shape of a rectangular block $300~\mathrm{cm}$ long, $50~\mathrm{cm}$ wide and $36~\mathrm{cm}$ high, a man
uses a cylindrical bucket, $30~\mathrm{cm}$ in diameter at its base and $48~\mathrm{cm}$ in height, to collect water from a fountain. Each time he goes to the fountain, he fills $\frac{4}{5}$ from the bucket and on the way spills $10\%$ of its contents. If the tank is initially empty, how many trips to the source will the man have to make for the water in the tank to reach $\frac{3}{4}$ of its height?
uses a cylindrical bucket, $30~\mathrm{cm}$ in diameter at its base and $48~\mathrm{cm}$ in height, to collect water from a fountain. Each time he goes to the fountain, he fills $\frac{4}{5}$ from the bucket and on the way spills $10\%$ of its contents. If the tank is initially empty, how many trips to the source will the man have to make for the water in the tank to reach $\frac{3}{4}$ of its height?