Có 5 hành khách bước ngẫu nhiên lên một đoàn tàu có 10 toa tính xác suất sao cho có 2 hành khách lên cùng một toa ba hành khách còn laị lên ba toa tàu khác

70,000 + 6,000 + 800 + 30

step-by-step explanation:

the answer for your question is

step-by-step explanation:

there is only one way to arrange all the eight relative to each other because they are not distinct. we have

now there are nine places to place an (and not more than one in one place).   because we have four symbols, we need to choose four of these nine places to insert an . order does not matter because the are not distinct.

thus there are 1 · c(9,4) ways, or, if we calculate it,

thus there are 126 ways to form such "words."