4/10 is equal to 2/5 because if you reduce 4/10 you get 2/5 which shows that they are equal.
Answer:
According to the passage, whales weight 300,000 pounds on average. Narwhales weigh 2,000 pounds on average.
Step-by-step explanation:
Since the question is extremely vague, I'll just answer what's the weight of whales and the weight of narwhals.
According to the paragraph, blue whales weigh 3×
pounds.
This is what we call scientific notation. You could solve it normally, or you could use a faster method.
Scientific notation states that the first number that you see, the three, is the first part of the answer. The exponent on the number of zero's that there is.
That means that the answer to 3×
you get 300,000.
Let's do the same thing to Narwhales.
2×
is 2,000.
We can solve this problem by referring to the standard
probability distribution tables for z.
We are required to find for the number of samples given the
proportion (P = 5% = 0.05) and confidence level of 95%. This would give a value
of z equivalent to:
z = 1.96
Since the problem states that it should be within the true
proportion then p = 0.5
Now we can find for the sample size using the formula:
n = (z^2) p q /E^2
where,
<span> p = 0.5</span>
q = 1 – p = 0.5
E = estimate of 5% = 0.05
Substituting:
n = (1.96^2) 0.5 * 0.5 / 0.05^2
n = 384.16
<span>Around 385students are required.</span>
1) Yes, the relationship in the table is proportional. If, when you've been walking for 10 minutes, you are 1.5 miles away from home, and when you've been walking for 20 minutes, you are 1 mile away from home, and when you've been talking 30 minutes, you are 0.5 miles away from home, then we can see that there is a proportion that happens here. For every 10 minutes you walk, you get 0.5 miles closer to your home.
2) We know that you've been walking 10 minutes already at the start of this problem, and we know that you walk at a steady pace of 0.5 miles every 10 minutes, so we just need to add 0.5 miles to our starting point to get the distance from the school to home, which makes it 2 miles away.
3) An equation representing the distance between the distance from school and time walking could be something like this:
t = 20d
Where t is the amount of time it takes to get home (in this case, t = 40 minutes) and d is the distance you can walk in 10 minutes (in this case, 0.5 miles)
The equation is lame, but that's the best I could do :\
Hope that helped =)