To fill a 15 gallon tank exactly halfway you'll need 7\(\frac{1}{2}\) gallons of fuel. Each fuel can holds 1\(\frac{1}{2}\) gallons so:

cans = \( \frac{7\frac{1}{2} \text{ gallons}}{1\frac{1}{2} \text{ gallons}} \) = 5

The area of a circle is given by the formula A = πr² where r is the radius of the circle. The radius of a circle is its diameter divided by two so A = π(\( \frac{d}{2} \))². If the diameter of the logo increases by 45% the radius (and, consequently, the total area) increases by \( \frac{45\text{%}}{2} \) = 22\(\frac{1}{2}\)%

If the tiger has consumed 28 pounds of food in 4 days that's \( \frac{28}{4} \) = 7 pounds of food per day. The tiger needs to consume 77 - 28 = 49 more pounds of food to reach 77 pounds total. At 7 pounds of food per day that's \( \frac{49}{7} \) = 7 more days.

To multiply fractions, multiply the numerators together and then multiply the denominators together:

\( \frac{1}{5} \) x \( \frac{3}{6} \) = \( \frac{1 x 3}{5 x 6} \) = \( \frac{3}{30} \) = \(\frac{1}{10}\)

To divide fractions, invert the second fraction and then multiply:

\( \frac{4}{7} \) ÷ \( \frac{3}{8} \) = \( \frac{4}{7} \) x \( \frac{8}{3} \)

To multiply fractions, multiply the numerators together and then multiply the denominators together:

\( \frac{4}{7} \) x \( \frac{8}{3} \) = \( \frac{4 x 8}{7 x 3} \) = \( \frac{32}{21} \) = 1\(\frac{11}{21}\)