Answer:
The river is 3.15 feet deep.
Step-by-step explanation:
First let's recognize what we need to find: the depth of the river
We know last year the river was 4.2 feet deep, but it dropped 25%. This means we also need to find how much it dropped. To find this, we need to know what 25% of 4.2 is. Write an equation for this.
y = 25% of 4.2
y = 0.25 • 4.2
y = 1.05
This means that the river dropped 1.05 feet. To know its depth now, we need to subtract 1.05 from 4.2. Write an equation for this.
d = 4.2 - 1.05
d = 3.15
The river is 3.15 feet deep.
Hope this helps!
Surface area is taking the area of each face and adding it together. The equation is 2lw + 2hw + 2hl. So, for example, you'd take the length and the width to the find the area of the top. Multiply this by 2 to find the top AND the bottom. You need to end with 6 sides and all these together to find your surface area.
1 Fluid ounce should be the answer.
Answer:
Step-by-step explanation:
Proportion of retired people under the age of 65 would return to work on a full-time basis if a suitable job were available = 60/100 = 0.6 = P
Null hypothesis: P ≤ 0.6
Alternative: P > 0.6
First, to calculate the hypothesis test, lets workout the standard deviation
SD = √[ P x ( 1 - P ) / n ]
where P = 0.6, 1 - P = 0.4, n = 500
SD = √[ (0.6 x 0.4) / 500]
SD = √ (0.24 / 500)
SD = √0.00048
SD = 0.022
To calculate for the test statistic, we have:
z = (p - P) / σ where p = 315/500 = 0.63, P = 0.6, σ = 0.022
z = (0.63 - 0.6) / 0.022
z = 0.03/0.022
z = 1.36
At the 2% level of significance, the p value is less than 98% confidence level, thus we reject the null hypothesis and conclude that more than 60% would return to work.
