Вопрос:

Solve the multiplication and division problems presented in the image.

Ответ:

Okay, let's break down each problem step by step. The key here is to remember how to multiply and divide fractions. When you have a problem like $\frac{a}{b} \cdot \frac{c}{d}$, you multiply the numerators (the top numbers) and the denominators (the bottom numbers) to get $\frac{a \cdot c}{b \cdot d}$. For division, $\frac{a}{b} : \frac{c}{d}$, you flip the second fraction and multiply: $\frac{a}{b} \cdot \frac{d}{c} = \frac{a \cdot d}{b \cdot c}$. Let's solve each one: 1. $\frac{8}{15} \cdot \frac{12}{120} \cdot \frac{30}{40}$ First, simplify before multiplying. Notice that 12/120 = 1/10, and 30/40 = 3/4. So the problem becomes $\frac{8}{15} \cdot \frac{1}{10} \cdot \frac{3}{4} = \frac{8 \cdot 1 \cdot 3}{15 \cdot 10 \cdot 4} = \frac{24}{600}$ Now simplify the result: $\frac{24}{600} = \frac{1}{25}$ 2. $\frac{4}{3} : \frac{12}{20} \cdot \frac{1}{5}$ Division first. $\frac{4}{3} : \frac{12}{20} = \frac{4}{3} \cdot \frac{20}{12} = \frac{80}{36}$ Simplify this to $\frac{20}{9}$ Now multiply by $\frac{1}{5}$ : $\frac{20}{9} \cdot \frac{1}{5} = \frac{20}{45} = \frac{4}{9}$ 3. $\frac{6}{10} \cdot \frac{5}{44} : \frac{2}{11}$ First, multiplication: $\frac{6}{10} \cdot \frac{5}{44} = \frac{30}{440} = \frac{3}{44}$ Now divide: $\frac{3}{44} : \frac{2}{11} = \frac{3}{44} \cdot \frac{11}{2} = \frac{33}{88} = \frac{3}{8}$ 4. $\frac{13}{50} : \frac{26}{12} : \frac{52}{13}$ First division: $\frac{13}{50} : \frac{26}{12} = \frac{13}{50} \cdot \frac{12}{26} = \frac{156}{1300} = \frac{3}{25}$ Second division: $\frac{3}{25} : \frac{52}{13} = \frac{3}{25} \cdot \frac{13}{52} = \frac{39}{1300} = \frac{3}{100}$ 5. $\frac{3}{9} \cdot \frac{1}{6} \cdot \frac{18}{72}$ Simplify first: $\frac{3}{9} = \frac{1}{3}$ and $\frac{18}{72} = \frac{1}{4}$ So, $\frac{1}{3} \cdot \frac{1}{6} \cdot \frac{1}{4} = \frac{1}{72}$ 6. $\frac{25}{10} : \frac{65}{90} : \frac{13}{45}$ First division: $\frac{25}{10} : \frac{65}{90} = \frac{25}{10} \cdot \frac{90}{65} = \frac{2250}{650} = \frac{45}{13}$ Second division: $\frac{45}{13} : \frac{13}{45} = \frac{45}{13} \cdot \frac{45}{13} = \frac{2025}{169}$ 7. $\frac{4}{7} \cdot \frac{2}{16} : \frac{2}{21}$ Multiplication: $\frac{4}{7} \cdot \frac{2}{16} = \frac{8}{112} = \frac{1}{14}$ Division: $\frac{1}{14} : \frac{2}{21} = \frac{1}{14} \cdot \frac{21}{2} = \frac{21}{28} = \frac{3}{4}$ 8. $\frac{54}{8} : \frac{27}{16} : \frac{2}{3}$ First division: $\frac{54}{8} : \frac{27}{16} = \frac{54}{8} \cdot \frac{16}{27} = \frac{864}{216} = 4$ Second division: $4 : \frac{2}{3} = 4 \cdot \frac{3}{2} = \frac{12}{2} = 6$ 9. $\frac{11}{99} \cdot \frac{9}{88} : \frac{8}{10}$ Multiplication: $\frac{11}{99} \cdot \frac{9}{88} = \frac{99}{8712} = \frac{1}{88}$ Division: $\frac{1}{88} : \frac{8}{10} = \frac{1}{88} \cdot \frac{10}{8} = \frac{10}{704} = \frac{5}{352}$ 10. $\frac{12}{18} : \frac{24}{9} : \frac{9}{48}$ First division: $\frac{12}{18} : \frac{24}{9} = \frac{12}{18} \cdot \frac{9}{24} = \frac{108}{432} = \frac{1}{4}$ Second division: $\frac{1}{4} : \frac{9}{48} = \frac{1}{4} \cdot \frac{48}{9} = \frac{48}{36} = \frac{4}{3}$ Now, let's solve the other side: 1. $\frac{17}{33} \cdot \frac{11}{34} = \frac{17 \cdot 11}{33 \cdot 34} = \frac{187}{1122} = \frac{1}{6}$ 2. $\frac{7}{30} \cdot \frac{6}{21} = \frac{7 \cdot 6}{30 \cdot 21} = \frac{42}{630} = \frac{1}{15}$ 3. $\frac{4}{12} \cdot \frac{18}{20} = \frac{4 \cdot 18}{12 \cdot 20} = \frac{72}{240} = \frac{3}{10}$ 4. $\frac{21}{25} \cdot \frac{15}{42} = \frac{21 \cdot 15}{25 \cdot 42} = \frac{315}{1050} = \frac{3}{10}$ 5. $\frac{14}{24} \cdot \frac{16}{21} = \frac{14 \cdot 16}{24 \cdot 21} = \frac{224}{504} = \frac{4}{9}$ 6. $\frac{50}{70} \cdot \frac{77}{150} = \frac{50 \cdot 77}{70 \cdot 150} = \frac{3850}{10500} = \frac{11}{30}$ 7. $\frac{23}{45} \cdot \frac{9}{46} = \frac{23 \cdot 9}{45 \cdot 46} = \frac{207}{2070} = \frac{1}{10}$ 8. $\frac{30}{66} \cdot \frac{77}{90} = \frac{30 \cdot 77}{66 \cdot 90} = \frac{2310}{5940} = \frac{7}{18}$ 9. $\frac{26}{32} \cdot \frac{12}{13} = \frac{26 \cdot 12}{32 \cdot 13} = \frac{312}{416} = \frac{3}{4}$ 10. $\frac{8}{19} \cdot \frac{38}{40} = \frac{8 \cdot 38}{19 \cdot 40} = \frac{304}{760} = \frac{2}{5}$
Убрать каракули
Смотреть решения всех заданий с фото

Похожие