大小齿轮的个数比是8:5,小齿轮有30个齿,大齿轮有______个齿.
30÷5×8,
=6×8,
=48(个);
答:大齿轮有48个齿.
故答案为:48.
Japan is ________ the east of China.
A. in B. on C. to
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