The result of rolling a number cube 7 times is a 7-digit number composed of digits 1,2,3,4,5 and 6 so that digits can repeat. The total number of possibilities is 6^7.
The number of possibilities where 4 appears exactly two times is 5^5*(7!-6!/2).
5^5 is the number of 5-digits numbers composed of digits 1,2,3,5 and 6 so that digits can repeat.
7! is the number of permutations of digits 1,2,3,4,4,5 and 6.
6! is the number of permutations of digits 1,2,3,{4,4},5 and 6.
We don't want to subtract all numbers where digits 4 appear side by side. That's why we must divide 6! by 2.
Finally, the probability is P=5^5(7!-6!/2)/7^7
Answer:
Step-by-step explanation:
52units
Answer:
The left side
−
2.875
is not greater than the right side
−
2.875
, which means that the given statement is false.
False
Step-by-step explanation:
For this case we must solve a system of two equations with two unknowns, given by "x" and "y".
We have:
We multiply (2) by -1:
We add (1) and (3):
Clearing x:
We substitute 
in (2)
Thus, the solution of the system is 
Answer:
The solution of the system is
If the question is referring to the least common multiple it is 24
