\[\boxed{\mathbf{1078\ (1078)}.\ Еуроки\ - \ ДЗ\ без\ мороки}\]
\[60\% = 0,6\]
\[52\% = 0,52\]
\[1)\ 1500 \cdot 0,6 = 15 \cdot 60 =\]
\[= 900\ (деревьев) -\]
\[фруктовые.\]
\[2)\ 900 \cdot 0,52 = 9 \cdot 52 =\]
\[= 468\ (деревьев) - вишневые.\]
\[Ответ:468\ вишневых\ деревьев.\]
\[\boxed{\mathbf{1078}\mathbf{.}\mathbf{\ }}\]
\[1)\frac{1^{\backslash 6}}{2}a + \frac{1^{\backslash 4}}{3}a - \frac{1^{\backslash 3}}{4}a =\]
\[= \frac{6 + 4 - 3}{12}a = \frac{7}{12}a\]
\[a = 1\frac{5}{7} = \frac{12}{7}:\]
\[\frac{7}{12}a = \frac{7 \cdot 12}{12 \cdot 7} = 1.\]
\[2)\ \frac{4^{\backslash 3}}{7}b + \frac{5}{21}b - \frac{2^{\backslash 7}}{3}b =\]
\[= \frac{12 + 5 - 14}{21}b = \frac{3}{21}b = \frac{1}{7}b\]
\[b = 2\frac{1}{3} = \frac{7}{3}:\]
\[\frac{1}{7}b = \frac{1 \cdot 7}{7 \cdot 3} = \frac{1}{3}.\]