The equation shown in the image is:

$\left( \frac{1}{4} \right)^{-3}$

To solve this:

1. Apply the negative exponent rule: When a fraction is raised to a negative exponent, we can flip the fraction and change the sign of the exponent. So:

$\left( \frac{1}{4} \right)^{-3} = \left( \frac{4}{1} \right)^3$

2. Simplify: Now, raise 4 to the power of 3:

$4^3 = 4 \times 4 \times 4 = 64$

Therefore:

$\left( \frac{1}{4} \right)^{-3} = 64$

So, the answer to the blank in the image should be 64.

Would you like a more detailed breakdown, or do you have any further questions?

---

Here are 5 questions for further practice:

1. What is $\left( \frac{1}{3} \right)^{-2}$?
2. How do you simplify $\left( \frac{2}{5} \right)^{-3}$?
3. What is the result of $\left( \frac{5}{6} \right)^{-2}$?
4. Can you explain the general rule for dealing with negative exponents?
5. How do you compute $\left( \frac{1}{2} \right)^{-4}$?

Tip: When you have a negative exponent, just flip the fraction to make the exponent positive!