ضرب الكسور — السنة الرابعة إعدادي

📐 الكسور التمرين 3 تمرين 3 من 6
3
أحسب وأعطِ النتيجة في صورة كسر مبسَّط :
\(A=\dfrac{4}{5}\times\dfrac{3}{8}\)
\(B=\dfrac{9}{2}\times\dfrac{5}{4}\)
\(C=\dfrac{9}{5}\times\dfrac{4}{-7}\)
\(D=\dfrac{4}{-3}\times\dfrac{-2}{-5}\)
\(E=\dfrac{4}{45}\times\dfrac{45}{4}\)
\(F=\dfrac{16}{45}\times\dfrac{16}{63}\)
\(G=\dfrac{27}{14}\times\dfrac{-90}{-56}\)
\(H=\dfrac{-30}{-48}\times\dfrac{36}{35}\)
لم تبدأ بعد

💡 الخطوة 1 — تبسيط قبل الضرب

\(\dfrac{\cancelto{1}{4}}{5}\times\dfrac{3}{\cancelto{2}{8}}\)
\(\text{لا تبسيط}\)
\(\text{لا تبسيط}\)
\(\text{لا تبسيط}\)
\(\dfrac{\cancelto{1}{4}}{\cancelto{1}{45}}\times\dfrac{\cancelto{1}{45}}{\cancelto{1}{4}}\)
\(\text{لا تبسيط}\)
\(\dfrac{27}{\cancelto{7}{14}}\times\dfrac{\cancelto{-45}{-90}}{-56}\)
\(\dfrac{\cancelto{-6}{-30}}{\cancelto{-4}{-48}}\times\dfrac{\cancelto{3}{36}}{\cancelto{7}{35}}\)

📝 الخطوة 2 — ضرب الأعداد المبسطة

\(\dfrac{1}{5}\times\dfrac{3}{2}=\dfrac{3}{10}\)
\(\dfrac{9}{2}\times\dfrac{5}{4}=\dfrac{45}{8}\)
\(\dfrac{9}{5}\times\dfrac{4}{-7}=\dfrac{36}{-35}\)
\(\dfrac{4}{-3}\times\dfrac{-2}{-5}=\dfrac{-8}{15}\)
\(\dfrac{1}{1}\times\dfrac{1}{1}=\dfrac{1}{1}\)
\(\dfrac{16}{45}\times\dfrac{16}{63}=\dfrac{256}{2835}\)
\(\dfrac{27}{7}\times\dfrac{-45}{-56}=\dfrac{-1215}{-392}\)
\(\dfrac{-6}{-4}\times\dfrac{3}{7}=\dfrac{-18}{-28}\)

✅ النتيجة النهائية

\(\dfrac{3}{10}\)
\(\dfrac{45}{8}\)
\(\dfrac{-36}{35}\)
\(\dfrac{-8}{15}\)
\(1\)
\(\dfrac{256}{2835}\)
\(\dfrac{1215}{392}\)
\(\dfrac{9}{14}\)