If $20\%$ of $45\%$ of a positive number is equal to $x$ percent of $0.3$ percent of the same number what is the value of $x$?

Question

I have tried setting up an equation and cross multiplying but it is not one of the answer choices.

Answer 1

You are right about the equation and cross multiplying, but as it was said in the comments, please for future questions if possible add always what you tried to do to solve the problem.

Unless I misunderstood the problem, I would do as follows, $n \gt 0$ is the positive number:

$\frac{20}{100}\cdot\frac{45}{100}\cdot n = \frac{x}{100}\cdot \frac{0.3}{100}\cdot n$

is the same as:

$\frac{20\cdot 45}{100\cdot 100}\cdot n = \frac{x\cdot 0.3}{100\cdot 100}\cdot n$

both sides are multiplied by $n$ and divided by $100\cdot 100$, so it is possible to simplify:

$20\cdot 45 = x\cdot 0.3$

finally:

$x=\frac{20\cdot45}{0.3}=3000$

Answer 2

Rewriting the worded problem into an equation, yield this below expression, out of which you can cancel out $p$ from both sides to get $x$.

$.20\times.45\times p=x\%\times0.3\%\times p\\ \implies0.09\times100\times100=x\times0.3\\ \implies x=3000$