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2 years ago

Leena knits 10 rows in 12 min. At this pace, how long will it take her to knit the next 25 rows?

Mathematics

2 answers:

amid [387]2 years ago

8 0

Answer:

62.5 minutes

Step-by-step explanation:

10 rows

------------ = 2/5 row/min

25 min

This is equivalent to 5/2 minutes per row.

Mult. this by 25 min to determine how many rows Leena can knit in that period:

5 min 25 rows

---------- * --------------- = 125/2 minutes, or 62.5 minutes

2 row 1

Flura [38]2 years ago

4 0

10 rows= 12 mins

there's 25 rows in all so break it down into 10, 10, and 5 to make it more simple

12+12= 24 minutes for 20 rows

since you only have 5 rows left (which is half of ten), you divide the 12 by two as well.

12mins/2= 6 minutes for 5 rows

24mins+6mins= 30 minutes

answer: It will take 30 minutes to knit 25 rows

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Jorge and Mary are both filling cups with fruit punch in preparation for a party. After 3 minutes, Jorge had 53 cups left to be

makkiz [27]

Answer:

Mary is filling 36 cups per minute, which is faster than Jorge.

Step-by-step explanation:

Lets get Jorge's time :

As the rate is constant, we can find the slope to know the number of cups he is filling per minute.

Slope is found using: $\frac{y2-y1}{x2-x1}$

= $\frac{53-25}{5-3}$

= $\frac{28}{2}=14$

From the table lets get Mary's time:

$\frac{99-81}{1-0.5}$

= $\frac{18}{0.5}=36$

Another data: $\frac{63-45}{2-1.5}$

= $\frac{18}{0.5}=36$

Therefore, we can see that Mary is filling 36 cups in a minute and Jorge is filling 14 cups.

Hence, the correct answer is : Mary is filling 36 cups per minute, which is faster than Jorge.

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2 years ago

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A bottle of white wine at room temperature (68°f) is placed in a refrigerator at 4 p.m. its temperature after t hr is changing a

Nat2105 [25]

After an hour (4pm to 5pm) the temperature drops 18e⁻⁰˙⁶=9.9℉, so the temperature after an hour will be 68-9.9=58.1℉.
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John Johnson is forty-seven. He is purchasing twenty-year endowment insurance, with a face value of $20,000. What is his annual

Alenkinab [10]

The answer is Letter D - 939.80.

You can refer to the attachment for the rate. Since he is forty-seven years old, use that age to find his rate under a twenty-year endowment insurance. In this case, the rate is 46.99. Multiply that rate to 20 since he purchased a 20-year endowment insurance with a face value of $20,000. (20,000/1,000 = 20)

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2 years ago

What’s 8/15 divided by 4/5

iragen [17]

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Step-by-step explanation: In this problem, we have 8/15 ÷ 4/5. Dividing by a fraction is the same as multiplying by its reciprocal. In other words, we can change the division sign to multiplication and flip the second fraction.

8/15 ÷ 4/5 can be rewritten as 8/15 × 5/4

Now, we are simply multiplying fractions so we multiply across the numerators and multiply across the denominators.

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2 years ago

A hospital finds that 22% of its accounts are at least 1 month in arrears. A random sample of 425 accounts was taken. What is th

GenaCL600 [577]

Answer:

8.85% probability that fewer than 82 accounts in the sample were at least 1 month in arrears

Step-by-step explanation:

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However, we are working with a large sample. So i am going to aproximate this binomial distribution to the normal.

Binomial probability distribution

Probability of exactly x sucesses on n repeated trials, with p probability.

Can be approximated to a normal distribution, using the expected value and the standard deviation.

The expected value of the binomial distribution is:

$E(X) = np$

The standard deviation of the binomial distribution is:

$\sqrt{V(X)} = \sqrt{np(1-p)}$

Normal probability distribution

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

When we are approximating a binomial distribution to a normal one, we have that $\mu = E(X)$ , $\sigma = \sqrt{V(X)}$ .