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3 years ago

Rich also has £400 pounds invest 3% compound interest . How many years does he need to invest the money to get at least £475

Mathematics

1 answer:

zepelin [54]3 years ago

7 0

Answer: 6 years

Step-by-step explanation:

Formula to calculate compound amount: $A=P(1+r)^t$ , where P= Principal , r=rate of interest, t= time

Given: P = £400, r = 3% = 0.03 , A= 475

Required equation: $400(1+0.03)^t\geq475$

$400(1.03)^t\geq475\\\\\Rightarrow\ (1.03)^t\geq\dfrac{475}{400}\\\\\Rightarrow\ (1.03)^t\geq1.1875$

Taking log on both sides , we get

$t \log 1.03\geq\log1.1875\\\\\Rightarrow\ t(0.0128372)\geq(0.0746336)\\\\\Rightarrow\ t\geq\dfrac{0.0746336}{0.0128372}=5.81385\approx6$

Hence, he needs to invest the money for 6 years to get atleast £475.

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Consider the population of all 1-gallon cans of dusty rose paint manufactured by a particular paint company. Suppose that a norm

Artemon [7]

Answer:

a) 0.5.

b) 0.8413

c) 0.8413

d) 0.6826

e) 0.9332

f) 1

Step-by-step explanation:

Problems of normally distributed samples are 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.

In this problem, we have that:

$\mu = 6, \sigma = 0.2$

(a) P(x > 6) =

This is 1 subtracted by the pvalue of Z when X = 6. So

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

$Z = \frac{6-6}{0.2}$

$Z = 0$

$Z = 0$ has a pvalue of 0.5.

1 - 0.5 = 0.5.

(b) P(x < 6.2)=

This is the pvalue of Z when X = 6.2. So

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

$Z = \frac{6.2-6}{0.2}$

$Z = 1$

$Z = 1$ has a pvalue of 0.8413

(c) P(x ≤ 6.2) =

In the normal distribution, the probability of an exact value, for example, P(X = 6.2), is always zero, which means that P(x ≤ 6.2) = P(x < 6.2) = 0.8413.

(d) P(5.8 < x < 6.2) =

This is the pvalue of Z when X = 6.2 subtracted by the pvalue of Z when X 5.8.

X = 6.2

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

$Z = \frac{6.2-6}{0.2}$

$Z = 1$

$Z = 1$ has a pvalue of 0.8413

X = 5.8

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

$Z = \frac{5.8-6}{0.2}$

$Z = -1$

$Z = -1$ has a pvalue of 0.1587

0.8413 - 0.1587 = 0.6826

(e) P(x > 5.7) =

This is 1 subtracted by the pvalue of Z when X = 5.7.

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

$Z = \frac{5.8-6}{0.2}$

$Z = -1.5$

$Z = -1.5$ has a pvalue of 0.0668

1 - 0.0668 = 0.9332

(f) P(x > 5) =

This is 1 subtracted by the pvalue of Z when X = 5.

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

$Z = \frac{5-6}{0.2}$

$Z = -5$

$Z = -5$ has a pvalue of 0.

1 - 0 = 1

5 0

3 years ago

The volume of a cube is 124 cubic inches.<br> What is the side length of the cube?

ivolga24 [154]

Answer:

4.987 in

Step-by-step explanation:

Volume of a cube= (where x= side)

x³

we know that

124=x³

∛124=x

x=4.986630952 which rounds to

4.987

8 0

3 years ago

Read 2 more answers

Tiana can clear a football field of debris in 3 hours. Jacob can clear the same field in 2 hours. If they decide to clear the fi

Marianna [84]

You must find the relative rates of both workers...

T=f/3 and J=f/2 so if they work together to clear the field then:

ft/3+ft/2=f make all terms have a common denominator of 6

(2/2)(ft/3)+(3/3)(ft/2)=(6/6)f

2ft/6+3ft/6=6f/6 multiply both sides by 6

2ft+3ft=6f divide both sides by f

2t+3t=6 combine like terms on left side

5t=6 divide both sides by 5

t=6/5 hr

t=1 1/5 hr

t=1 hr 12 min

8 0

3 years ago

An expression is shown below

Leno4ka [110]

Answer:

B) It is irrational and equal to $= 4\sqrt{2}$

Step-by-step explanation:

The expression, $\sqrt{18} + \sqrt{2}$ , is an irrational expression because it contains two irrational numbers, $\sqrt{18}$ and $\sqrt{2}$ . Both number are not perfect square. there is no whole number that would be squared that will give you 18 nor 2.