I assume you mean the product of mixed numbers,
3 1/2 × 3 1/2
If we write this as
(3 + 1/2) × (3 + 1/2) = (3 + 1/2)²
we can use the identity
(a + b)² = a² + 2ab + b²
so that
3 1/2 × 3 1/2 = 3² + (2 × 3 × 1/2) + (1/2)²
3 1/2 × 3 1/2 = 9 + 3 + 1/4
3 1/2 × 3 1/2 = 12 1/4
Alternatively, we can first write 3 1/2 as a mixed number:
3 + 1/2 = 6/2 + 1/2 = (6 + 1)/2 = 7/2
Then
3 1/2 × 3 1/2 = 7/2 × 7/2 = (7 × 7) / (2 × 2) = 49/4
and
49/4 = (48 + 1)/4 = ((4 × 12) + 1)/4 = 12 + 1/4
Because 1/4 is a fractional number, it is also a ratio which means it is Rational. :)
Answer:
The 99% confidence interval for the mean peak power after training is [299.4, 330.6]

Step-by-step explanation:
We have to construct a 99% confidence interval for the mean.
A sample of n=7 males is taken. We know the sample mean = 315 watts and the sample standard deviation = 16 watts.
For a 99% confidence interval, the value of z is z=2.58.
We can calculate the confidence interval as:

The 99% confidence interval for the mean peak power after training is [299.4, 330.6]
Answer:
1598.2
Step-by-step explanation:
I used a calculator on this one.
1,224 minutes.
75.20 minus 14 = 61.2
61.2 / 1,224minutes