36.45 is what percent of 81? Choose matching definition 40% 30% 45% 50%

To find what percent 36.45 is of 81, we can set up a proportion:<br /><br />\[<br />\frac{36.45}{81} = \frac{x}{100}<br />\]<br /><br />where \( x \) is the percentage we are looking for.<br /><br />First, we solve for \( x \):<br /><br />\[<br />x = \frac{36.45 \times 100}{81}<br />\]<br /><br />Now, perform the calculation:<br /><br />\[<br />x = \frac{3645}{81} \approx 45<br />\]<br /><br />So, 36.45 is approximately 45% of 81.<br /><br />Therefore, the correct answer is:<br /><br />$45\% $