(√5 + 3)² / √20=
((√5 + 3)² / √20)(√20/√20)=
(√20(√5 + 3)²) / (√20)²=
√20(5+6√5+9) /20=
√20 (14+6√5) /20=
(14√20 +6√100) /20=
(14√20 +60) / 20=
(14(√4√5) + 60) /20=
(14(2)(√5)+60) / 20=
(28√5+60) /20=
(7√5+15) / 5
Answer:(√5 + 3)² / √20= <span>(7√5+15) / 5</span>
Answer:
Step-by-step explanation:
Total number of days
The number of days she bought a banana or orange
The probability of buying a banana or an orange is
- P(b or o) = 21/30 = 0.7 = 70%
Answer: 2343
Step-by-step explanation:
Answer:
a) 
With:


b) 

c) 

d) 


Step-by-step explanation:
For this case we know the following propoertis for the random variable X

We select a sample size of n = 81
Part a
Since the sample size is large enough we can use the central limit distribution and the distribution for the sampel mean on this case would be:

With:


Part b
We want this probability:

We can use the z score formula given by:

And if we find the z score for 89 we got:


Part c

We can use the z score formula given by:

And if we find the z score for 75.65 we got:


Part d
We want this probability:

We find the z scores:


