(2890+5/6+7/8+7/10)÷(5/6+7/8+7/10)
问题描述:
(2890+
+5 6
+7 8
)÷(7 10
+5 6
+7 8
) 7 10
答
设
+5 6
+7 8
为a,7 10
(2890+
+5 6
+7 8
)÷(7 10
+5 6
+7 8
)7 10
=(2890+a)÷a,
=2890÷a+a÷a,
=2890÷a+1,
=2890÷(
+5 6
+7 8
)+1,7 10
=2890÷
+1,289 120
=1200+1,
=1201.