SAT 2 maths

来源：学生作业帮编辑：大师作文网作业帮分类：英语作业时间：2024/11/10 11:37:34

SAT 2 maths
A coin is tossed three times.given that at least one head appears.what is the probability that exactly two heads appear?
Answer 3/7 为什么不是3/8?

因为题目说至少有一面朝上了,所以排除掉三面都朝下的可能,就是3/7了

SAT 2 maths level2 SAT 2 maths help~2 条 F.2 maths question~ 2道SAT数学题... sat SAT 2数学用计算器吗 sat语法2题目. 2道sat grammar题目, maths question maths problem maths problems! easy maths