A dice is rolled six times. One, two, three, four, five and six appears on consecutive throws of dices. How many ways are possible having 1 before 6?
\(\large \color{black}{\begin{align} & \normalsize \text{ A dice is rolled six times. }\hspace{.33em}\\~\\ & \normalsize \text{ One, two, three, four, five and six appears on consecutive throws of dices.}\hspace{.33em}\\~\\ & \normalsize \text{ How many ways are possible having 1 before 6?}\hspace{.33em}\\~\\ \end{align}}\)
if 1 occurs on the first throw ether are 5! ways . Agreed? I'm never 100% confident on these counting questions!!
ok
so I guess we have to consider the scenario when occurs on the second throw. when 6 occurs on the first throw we have to discount these arrangements
* when 1 occurs
so that is -4!
negative 4! ?
No sorry - we just ignore those
if no 6 on first throw there are 4 * 4! ways right?
how does that come
is the answer (5!)^2 ?
well you have any number between 2 and 5 on first throw and there are 4! arrangements of the other 4
|dw:1442759227308:dw|
in book it is given as 6!/2=360
sry i did a silly mistake well- |dw:1442759335031:dw| like this make cases nd then u get tota ways= 5!+4*4!+3*4!+2*4!+1*4!=360
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