13.108. On the plots allocated by the agrolaboratory for experiments, $c$ from two plots, 14.7 tons of grain were collected. The next year, after the application of new agricultural techniques, the yield on the first plot increased by $80 \%$, and on the second - by $24 \%$, as a result of which from these same plots, 21.42 tons of grain were collected. How many tons of grain are collected from each plot after the application of new agricultural techniques?
## Solution.

Let $x$ tons of grain be collected from the first plot after the application of new methods, and $y$ tons - from the second plot. According to the condition, $x+y=21.42$. Initially, $\frac{x}{1.8}$ tons were collected from the first plot, and $-\frac{y}{1.24}$ tons from the second plot. According to the condition, $\frac{x}{1.8}+\frac{y}{1.24}=14.7$. Solving the system $\left\{\begin{array}{l}x+y=21.42 \\ \frac{x}{1.8}+\frac{y}{1.24}=14.7,\end{array}\right.$ we find $x=10.26$ tons; $y=11.16$ tons.

Answer: 10.26 and $11.16$ tons.