4500 + 1.20x < 4.80x
4500 < 4.80x - 1.20x
4500 < 3.60x
4500/3.60 < x
1250 < x.......minimum number would be 1251
Answer:
3.4
Step-by-step explanation:
Standard deviation of a population is defined as:
σ² = ∑(xᵢ − μ)² / n
The standard deviation of a sample is defined as:
s² = ∑(xᵢ − x)² / (n - 1)
It's not clear which one we have, so let's calculate both.
First, we must find the mean.
μ = (5+12+15+10+12+6+8+8) / 8
μ = 9.5
Now we find the squares of the differences:
(5-9.5)² + (12-9.5)² + (15-9.5)² + (10-9.5)² + (12-9.5)² + (6-9.5)² + (8-9.5)² + (8-9.5)²
= 80
Divide by n:
σ² = 80 / 8
σ² = 10
And take the square root:
σ = √10
σ ≈ 3.2
That's not one of the answers, so let's try the standard deviation of a sample instead of a population.
Instead of dividing by n, we'll divide by n-1:
s² = 80 / 7
And take the square root:
s = √(80/7)
s ≈ 3.4
So that must be it.
Answer:
$19.10
Step-by-step explanation:
So since he charges $1.85 for the first quarter mile we can keep that as it is for now. If we add 0.25 4 times to make it $1 that would be a mile. We just have to add $17.25 plus the original $1.85 fee
Answer:
Round 34 down to 30 then round 39 up to 40
Step-by-step explanation:
34 ⟶ 30 34 is rounded down to 30
39 ⟶ 40 39 rounded up to 40
34 ⟶ 30
39 ⟶ 40
34 is rounded down to 30
39 rounded up to 40
Calculate mentally 34 × 39 = 1326
The estimated product is 1326.
