A certain concrete mixture is made of cement, sand, and soil, in the ratio of $1: 3: 5$ per kilogram. How many kilograms of this mixture can be made with 5 kilograms of cement?
(a) $13 \frac{1}{3}$
(b) 15
(c) 25
(d) 40
(e) 45
The correct option is (e).

According to the data in the problem, we mix $1 \mathrm{~kg}$ of cement with $3 \mathrm{~kg}$ of sand and $5 \mathrm{~kg}$ of soil. This is equivalent to mixing $5 \mathrm{~kg}$ of cement with $15 \mathrm{~kg}$ of sand and $25 \mathrm{~kg}$ of soil, and this mixture weighs $5+15+25=45 \mathrm{~kg}$.