Hello everyone!

I am strungling a bit here, so if any1 can help , its much appreciated!

How many 8-bit sequences there are, which consist of:

• Exactly 2 acces (2x1s ,6x0s)
• Exactly 4 acces (4x1s, 4x0s)
• Exactly 6 acces (6x1s, 2x0s)
• At least 6 acces

 

Hello everyone!

I am strungling a bit here, so if any1 can help , its much appreciated!

How many 8-bit sequences there are, which consist of:

• Exactly 2 acces (2x1s ,6x0s)
• Exactly 4 acces (4x1s, 4x0s)
• Exactly 6 acces (6x1s, 2x0s)
• At least 6 acces

I think it would be ...

P(exactly 2)=8C2=28
P(exactly 4)=8C4=70

etc

P(at least 6)=P(6)+P(7)+P(8)=8C6+8C7+8C8

where nCr = combinations rule (on your calculator)

 

thanks a lot =) , hope its right !