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
Greetings!
Solve for d.

Distribute the Parenthesis.



Reduce.

Add
-2/3 to both sides.

Simplify.


Add
-1/4d to both sides.

Simplify.


Divide both sides by
-1/12.

Simplify.


Reduce.


Hope this helps.
-Benjamin
Answer:
942
Step-by-step explanation :
so your d is 300 so your r = 300/2= 150
a=3.14*r*r= 3.14*150*150= 70650
c= 3.14*d= 3.14*300= 942
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OR
The curved surface area of solid cylinder is
As we are given that:
Diameter of solid cylinder = 8 cm
Length or Height o solid cylinder = 140 cm
Formula used to calculate the curved surface area of cylinder is:2n x h
Curved surface area of cylinder =2r x h
where,
r = radius of cylinder
h = height or length of cylinder
Radius of cylinder = daimeter
Now putting all the given values in above formula, we get:
Curved surface area of cylinder = 2x 22/7 x 140cm
Curved surface area of cylinder = 
Therefore, the curved surface area of solid cylinder is3520cm^{2}