We are given the equation \( t\% \) of 40% of 100 is equal to 20% of 300. Let us first express both sides of the equation mathematically.
The left side is:
\[
\frac{t}{100} \times \left( 40\% \times 100 \right) = \frac{t}{100} \times 40
\]
Simplifying this:
\[
\frac{t}{100} \times 40 = \frac{40t}{100} = \frac{2t}{5}
\]
The right side is:
\[
20\% \times 300 = \frac{20}{100} \times 300 = 60
\]
Now we equate both sides of the equation:
\[
\frac{2t}{5} = 60
\]
Multiply both sides of the equation by 5 to eliminate the denominator:
\[
2t = 60 \times 5 = 300
\]
Step 4: Divide both sides by 2 to solve for \( t \):
\[
t = \frac{300}{2} = 150
\]
To solve percentage problems, simplify the equation step by step, focusing on reducing percentages to decimals when necessary.