A number when decreased by 16% becomes 798; find the number.

Let the number be $x$.

The number is decreased by 16%.

∴ Amount by which the number is decreased = 16% of $x$

= $\dfrac{16}{100} \times x$

= $\dfrac{16x}{100}$

Given, the decreased number becomes 798,

$\therefore x - \dfrac{16x}{100} = 798 \\[1em] \Rightarrow \dfrac{100x - 16x}{100} = 798 \\[1em] \Rightarrow \dfrac{84x}{100} = 798 \\[1em] \Rightarrow x = \dfrac{798 \times 100}{84} \\[1em] \Rightarrow x = \dfrac{79,800}{84} \\[1em] \Rightarrow x = 950$

Hence, the number is 950.