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3 years ago

you invested 1,000 in an account with interest rate at 2% compounded continuously. how long until 1400 is in your account?

Mathematics

1 answer:

Tanya [424]3 years ago

5 0

Answer:20 months

Step-by-step explanation:

2% of 1000 is 20 1000-1400=400

400/20=20 so 20 months

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Math help pls,,, thank you !! will reward. <3

TiliK225 [7]

Answer:

Step-by-step explanation:

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4 0

3 years ago

Here are the first four terms of a sequence.

Nataly_w [17]

Answer:

aₙ = 2n² + n + 1

Step-by-step explanation:

We observe that the difference of terms is 4, 7 and 15 and next level difference is 4. It means the sequence is quadratic.

We can compare this with simple quadratic sequence

1, 4, 9, 16

and find out that doubling each term gives us

2, 8, 18, 32

This is close to our sequence, write the terms as follows to find exact rule

The first term:

a₁ = 4 = 2*1² + 2 = 2*1² + 1 + 1

The second term

a₂ = 11 = 2*2² + 3 = 2*2² + 2 + 1

The third term:

a₃ = 22 = 2*3² + 4 = 2*3² + 3 + 1

The fourth term:

a₄ = 37 = 2*4² + 5 = 2*4² + 4 + 1

The nth term as per observation above is:

aₙ = 2n² + n + 1

8 0

3 years ago

A half-century ago, the mean height of women in a particular country in their 20s was 64.7 inches. Assume that the heights of

Ainat [17]

Answer:

99.5% of all samples of 21 of today's women in their 20's have mean heights of at least 65.86 inches.

Step-by-step explanation:

We are given that a half-century ago, the mean height of women in a particular country in their 20's was 64.7 inches. Assume that the heights of today's women in their 20's are approximately normally distributed with a standard deviation of 2.07 inches.

Also, a samples of 21 of today's women in their 20's have been taken.

Let $\bar X$ = sample mean heights

The z-score probability distribution for sample mean is given by;

Z = $\frac{\bar X -\mu}{\frac{\sigma}{\sqrt{n} } }$ ~ N(0,1)

where, $\mu$ = population mean height of women = 64.7 inches

$\sigma$ = standard deviation = 2.07 inches

The Z-score measures how many standard deviations the measure is away from the mean. After finding the Z-score, we look at the z-score table and find the p-value (area) 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.

Now, Probability that the sample of 21 of today's women in their 20's have mean heights of at least 65.86 inches is given by = P( $\bar X$ $\geq$ 65.86 inches)

P( $\bar X$ $\geq$ 65.86 inches) = P( $\frac{\bar X -\mu}{\frac{\sigma}{\sqrt{n} } }$ $\geq$ $\frac{65.86-64.7}{\frac{2.07}{\sqrt{21} } }$ ) = P(Z $\geq$ -2.57) = P(Z $\leq$ 2.57)