+592 1 ft = 12 inch.
This means the small one's height is \(\frac{10}{12}\) ft.
\(4 \div \frac{10}{12} = \frac{24}{5}\)
d = \(10 \div \frac{24}{5} = \frac{25}{12}\)
This means d = 25 inches.
edit: it might be easier to change feet into inches. I just did it this way
