ضرب الكسور — السنة الرابعة إعدادي

📐 الكسور التمرين 5 تمرين 5 من 6
5
أحسب وأعطِ النتيجة في صورة كسر مبسَّط :
\(A=\dfrac{1}{8}\times\dfrac{1}{5}\)
\(B=\dfrac{9}{2}\times\dfrac{1}{4}\)
\(C=\dfrac{3}{5}\times\dfrac{-2}{-9}\)
\(D=\dfrac{-4}{-3}\times\dfrac{-10}{-3}\)
\(E=\dfrac{28}{27}\times\dfrac{16}{9}\)
\(F=\dfrac{2}{15}\times\dfrac{9}{8}\)
\(G=\dfrac{16}{45}\times\dfrac{-45}{-24}\)
\(H=\dfrac{21}{80}\times\dfrac{-3}{-64}\)
لم تبدأ بعد

💡 الخطوة 1 — تبسيط قبل الضرب

\(\text{لا تبسيط}\)
\(\text{لا تبسيط}\)
\(\dfrac{\cancelto{1}{3}}{5}\times\dfrac{-2}{\cancelto{-3}{-9}}\)
\(\text{لا تبسيط}\)
\(\text{لا تبسيط}\)
\(\dfrac{\cancelto{1}{2}}{\cancelto{5}{15}}\times\dfrac{\cancelto{3}{9}}{\cancelto{4}{8}}\)
\(\dfrac{\cancelto{2}{16}}{\cancelto{1}{45}}\times\dfrac{\cancelto{-1}{-45}}{\cancelto{-3}{-24}}\)
\(\text{لا تبسيط}\)

📝 الخطوة 2 — ضرب الأعداد المبسطة

\(\dfrac{1}{8}\times\dfrac{1}{5}=\dfrac{1}{40}\)
\(\dfrac{9}{2}\times\dfrac{1}{4}=\dfrac{9}{8}\)
\(\dfrac{1}{5}\times\dfrac{-2}{-3}=\dfrac{-2}{-15}\)
\(\dfrac{-4}{-3}\times\dfrac{-10}{-3}=\dfrac{40}{9}\)
\(\dfrac{28}{27}\times\dfrac{16}{9}=\dfrac{448}{243}\)
\(\dfrac{1}{5}\times\dfrac{3}{4}=\dfrac{3}{20}\)
\(\dfrac{2}{1}\times\dfrac{-1}{-3}=\dfrac{-2}{-3}\)
\(\dfrac{21}{80}\times\dfrac{-3}{-64}=\dfrac{-63}{-5120}\)

✅ النتيجة النهائية

\(\dfrac{1}{40}\)
\(\dfrac{9}{8}\)
\(\dfrac{2}{15}\)
\(\dfrac{40}{9}\)
\(\dfrac{448}{243}\)
\(\dfrac{3}{20}\)
\(\dfrac{2}{3}\)
\(\dfrac{63}{5120}\)