1. If 18 is $\frac{2}{3}$ of a number, what is the number? ___
2. A car's fuel tank is $\frac{3}{5}$ full. If it contains 9 gallons of gas, what is the total capacity of the tank in gallons?
3. The value 45 represents $\frac{5}{9}$ of an unknown number. The unknown number is ___.
4. If 24 is $\frac{4}{7}$ of a number, what is the first step to find the value of one unit part?
5. If 21 is $\frac{7}{3}$ of a number, what is that number? ___
6. You used 120 grams of flour, which is $\frac{3}{4}$ of the amount a recipe requires. How many grams of flour does the recipe require in total?
7. If 36 is $\frac{4}{5}$ of a whole, the value of the whole is ___.
8. A sale price of an item is 30 dollars. This price is $\frac{6}{5}$ of the original price. What was the original price?
9. If $\frac{1}{2}$ of the water in Tank A is equal to $\frac{3}{5}$ of the water in Tank B, and the total volume is 110 liters, what is the volume in Tank A in liters? ___
10. If $\frac{2}{3}$ of the red marbles in a bag equals $\frac{4}{7}$ of the blue marbles, what is the ratio of the number of red marbles to blue marbles?