1. 8/15 : 20/21 ; 39/43 : 13/43 ; 21/22 : 7/18 ; 44/45 : 11/18 помогите пожалуйста!!!

$1)\frac{8}{15} \div \frac{20}{21} = \frac{8}{15} \times \frac{21}{20} = \frac{8 \times 21}{15 \times 20} = \frac{2 \times 7}{5 \times 5} = \frac{14}{25}$

$2)\frac{39}{43} \div \frac{13}{43} = \frac{39}{43} \times \frac{43}{13} = \frac{39 \times 43}{43 \times 13} = \frac{3 \times 1}{1 \times 1} = 3$

3) $\frac{21}{22} \div \frac{7}{18} = \frac{21}{22} \times \frac{18}{7} = \frac{21 \times 18}{22 \times 7} = \frac{3 \times 9}{11 \times 1} = \frac{27}{11} = 2 \frac{5}{11}$

4) $\frac{44}{45} \div \frac{11}{18} = \frac{44}{45} \times \frac{18}{11} = \frac{44 \times 18}{45 \times 11} = \frac{4 \times 2}{5 \times 1} = \frac{8}{5} = 1 \frac{3}{5}$