Числовой луч:
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0 1 2 3 4 5 6 7
1 = $$\frac{1 \cdot 8}{8} = \frac{8}{8}$$
$$1\frac{7}{8} = \frac{1 \cdot 8 + 7}{8} = \frac{8 + 7}{8} = \frac{15}{8}$$
2 = $$\frac{2 \cdot 8}{8} = \frac{16}{8}$$
$$2\frac{5}{8} = \frac{2 \cdot 8 + 5}{8} = \frac{16 + 5}{8} = \frac{21}{8}$$
3 = $$\frac{3 \cdot 8}{8} = \frac{24}{8}$$
$$3\frac{1}{8} = \frac{3 \cdot 8 + 1}{8} = \frac{24 + 1}{8} = \frac{25}{8}$$
Ответ: $$\frac{8}{8}, \frac{15}{8}, \frac{16}{8}, \frac{21}{8}, \frac{24}{8}, \frac{25}{8}$$.