Answer:
n = 61 costumers
Step-by-step explanation:
For calculating the number of costumers he should sample we use the next equation:

Where E is the error that we are prepared to accept, in this case E = 0.15
How we don't know the value of p, we can estimate it like p = 0.5
∝ = 1-0.98 = 0.02
1-∝/2 = 0.99


n = 60.32 costumers
n ≈ 61 costumers
Your drawing was much more helpful and informative than your statements in words and symbols.
I see that you want to evaluate (3/2)^2 times (8/15)^2.
You could combine these two expressions into one, as follows:
3*8
( ----------- )^2
2*15
This, in turn, can be simplified by reduction:
( 4/5 )^2. Expanded, this result gives us 16/25.
Next problem
----------------------------
( 9/4 )^4 * ( 4/3 )^3
9^4 4^3
First, focus on ( ------- ) * ( ----------- )
4^4 3^3
Now reduce 4^3 / 4^4: The end result is 1/4.
Reduce 9^4 / 3^3. To do this, rewrite that 9 as (3^2), resulting in:
3^8 / 3^3. The end result is 3^5.
Putting this expression back together, we get 3^5 / 4 (answer)
1. You could break them up:
10+30+20+10=70
6+5+4+4=19
70+19=89
2. Separate to groups:
16+35=51
24+14=38
51+38=89
Answer:
$2.25 per ft² (I think)
Step-by-step explanation:
Subtract 4.9 from 6.4 to get 1.5
Multiply 6.4 by 1.5 and multiply 4.9 by 1.5
Then you get 9.6 and 7.35
Subtract 7.35 from 9.6 and get 2.25