83. What is in the period? Determine what stands in the period of the decimal expansion of the fraction $\frac{1}{49}$.[^3]
83. If we limit ourselves to the first period in the decimal expansion of the number $\frac{1}{7}$, we get 0.142857. Repeating this period 7 times and dividing the resulting number by 7, there will be no remainder*. The result is the first period of the decimal expansion of the number $\left(\frac{1}{7}\right)^{2}$. Thus,

$$
\begin{aligned}
& 0.142857142857142857142857142857142857142857: 7= \\
& =0.020408163265306122448979591836734693877551
\end{aligned}
$$

[D. K. Duncan, M. M., 25, 224 (March 1952).][^26]