Translate to an equation and solve. Let $\mathrm{x}$ be the unknown number. $120 \%$ of what number is $66 ?$ $x=\square$ (Type an integer or a decimal.)

Step 1 ：\(\frac{120}{100} \times x = 66\)

Step 2 ：\(x = \frac{66}{\frac{120}{100}}\)

Step 3 ：\(x = \frac{66}{1.2}\)

Step 4 ：\(\boxed{55}\)