Answer:
(a) 720 ways
(b) 120 ways
(c) 24 ways
Step-by-step explanation:
Given

--- number of letters
Solving (a): Number of arrangements.
We have:

So, the number of arrangements is calculated as:

This gives:

This gives:


Solving (b): DA as a unit
DA as a unit implies that, we have:
[DA] N C E R
So, we have:

So, the number of arrangements is calculated as:

This gives:

This gives:


Solving (c): NCE as a unit
NCE as a unit implies that, we have:
D A [NCE] R
So, we have:

So, the number of arrangements is calculated as:

This gives:

This gives:


Its the red one bc its between 1 and 12
Answer:
that looks like it is right
Answer:
P = 7.14%
The percentage of those 30 years or older that own an ipod is 7.14%
Step-by-step explanation:
Given;
Percentage of ipod owners Pi = 20%
Percentage who don't own ipod Pd = 100-20 = 80%
For age 30 or older;
Percentage of ipod owners who belong to this group
Po = 20% of Pi
Percentage who don't have an ipod but belong to this group Pu = 100-35% = 65% of Pd
The percentage of those 30 years or older that own an ipod is;
P = Po/(Po+Pu) × 100%
Po = 20% of Pi = 20% of 20% = 0.2×20 =4%
Pu = 65% of Pd = 65% of 80% = 0.65×80% = 52%
Substituting the values;
P = 4/(4+52) × 100%
P = 7.14%