王大爷买24只小鸡花了72元钱,他还要再买50只这样的小鸡,王大爷还要花多少元钱?
72÷24×50,
=3×50,
=150(元).
答:王大爷还要花150元钱.
用动词的适当形式填空。
1. Last summer, I _______ (swim) in the swimming pool.
2. I will _______ (play) table tennis.
3. The boy will _______ (put) on his shoes and play outside.
4. Mr. Wood _______ (teach) us very well.
5. Danny _______ (walk) to school every day.
简述股票投资风险的主要种类及其防范。