Ro. Para hacer una obra, 15 operarios emplean 18 días, ¿cuántos días hubieran empleado 10 operarios? Una camiseta cuesta \( 25 € \).

10. \( 90-45 \)

A pool in the shape of a rectangular prism has dimensions of 8 meters long, 6 meters wide, and 2 meters deep. If the pool is empty, how many liters of water can it hold when full? (Note: 1 cubic meter = 1000 liters)

3. When the positive integers \( a, b \) and \( c \) are divided by 13 , the respective remainders are 9,7 and 10 , respectively. Show that \( a+b+c \) is divisible by 13 .

2. \( 2.45-17 \)

2. The equivalent fraction of \( \frac{64}{56} \) with denominator 7 is \( \begin{array}{llll}\text { a) } \frac{6}{7} & \text { b) } \frac{9}{7} & \text { c) } \frac{7}{8} & \text { d) } \frac{8}{7}\end{array} \)