Step-by-step explanation:
Here we are given that , the Value of
And we need to find the prove that ,
We know a identity as ,
On cubing both sides of the given equation,
Simplify and then substitute ,
Hence Proved !
Answer:
Mrs. Barnes washed more.
Step-by-step explanation:
We have been given that on the day of his 18th birthday Harry decided to start saving money regularly
. Starting on that day, he could save 30.00 on the same date every month. We are asked to find the amount saved by the day before Harry's 60th birthday.
First of all, we will find years from 18 years to 60 years.

We know that 1 year equals 12 months.

To find total amount saved, we will multiply 504 months by amount saved per month.


Therefore, Harry would have saved
by the day before his 60th birthday.
Answer: n = 14
Step-by-step explanation: margin of error = critical value × σ/√n
Where σ = population standard deviation = 1
n = sample size = ?
We are to construct a 99% confidence interval, hence the level of significance is 1%.
The critical value for 2 tailed test at 1% level of significance is gotten from a standard normal distribution table which is 2.58
Margin of error = 0.7
0.7 = 2.58×1/√n
0.7 = 2.58/√n
By cross multipying
0.7×√n = 2.58
By squaring both sides
0.7^2 × n = 2.58^2
0.49 × n = 6.6564
n = 6.6564/0.49
n = 14