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2 years ago

Which number in the monomial 125x18y3z25 needs to be changed to make it a perfect cube?

2 answers:

7 0

To make the monomial 125 x^18 y^3 z^25 a perfect cube, the entire expression should be reduced to a rational number when the cube root is taken. For the constant 125, the cube root is 5, so it doesn't need to be changed. For the variables, the exponents should be divisible by 3. The exponent of z is not divisible by 3. It can be subtracted with 1 or added with 2 to make the expression a perfect cube.

Fofino [41]2 years ago

4 0

Answer: Option 3(C)

Got it right on ED 2020, Good luck!! :)

You might be interested in

Which pair of rational numbers are equivalent? 1/3 and 0.3 2/5 and 0.25 5/6 and 0.833... 9/10 and 0.09

tatyana61 [14]

5/6 and 0.833
Hope this helped

3 0

1 year ago

Read 2 more answers

1. Three friends pooled their money to purchase a new game system that costs $298. One person

iragen [17]

Answer:

First person: $107

Second person: $98

Third person: $93

Step-by-step explanation:

Let be "f" the amount of money (in dollars) that the first person contributed to the purchase, "s" the amount of money (in dollars) that the second person contributed to the purchase and "t" the amount of money (in dollars) that the third person contributed to the purchase.

With the information given in the exercise, you can set up the following equations:

Equation 1 → $f+s+t=298$

Equation 2 → $s=f-9$

Equation 3 → $t=f-14$

Substitute the Equations 2 and 3 into the Equation 1 and then solve for "f":

$f+(f-9)+(f-14)=298\\\\3f-23=298\\\\f=\frac{321}{3}\\\\f=107$

Finally, substitute the value of "f" into the Equation 2 and then into the Equation 3, in order to find the values of "s" and "t".

Therefore, you get:

$s=107-9\\\\s=98\\\\\\t=107-14\\\\t=93$

5 0

1 year ago

Jim's work evaluating 2 (three-fifths) cubed is shown below. 2 (three-fifths) cubed = 2 (StartFraction 3 cubed Over 5 EndFractio

Blizzard [7]

Answer:

$2(\frac{3}{5}) ^{3}=2(\frac{3^3}{5^3})$ and not $2(\frac{3}{5}) ^{3}=2(\frac{3^3}{5})$

Step-by-step explanation:

Jim's work evaluating $2(\frac{3}{5}) ^{3}$ is shown:

$2(\frac{3}{5}) ^{3}=2(\frac{3^3}{5})=2(\frac{3X3X3}{5})=2(\frac{27}{5})=\frac{54}{5}$

If you look at the Second step, the exponent is taken over only the numerator. It should have been taken over both the numerator and denominator as shown below.

$2(\frac{3}{5}) ^{3}=2(\frac{3^3}{5^3})$

The correct workings therefore is:

$2(\frac{3}{5}) ^{3}=2(\frac{3^3}{5^3})=2(\frac{3X3X3}{5X5X5})=2(\frac{27}{125})=\frac{54}{125}$

7 0

2 years ago

Read 2 more answers

The formula for percentage increase I (given as a decimal) of an investment is I=S−PP, where P is the purchase price and S is th

sattari [20]

18.75/75=(75/75) -
p =(75-18.5)/75
p=56.5/75
p=0.75(3recurring)

5 0

1 year ago

Read 2 more answers

Consider the following random sample from a normal population: 14, 10, 13, 16, 12, 18, 15, and 11. What is the 95% confidence in

seraphim [82]

Answer:

$13.625-2.365\frac{2.669}{\sqrt{8}}=11.393$

$13.625+2.365\frac{2.669}{\sqrt{8}}=15.857$

So on this case the 95% confidence interval would be given by (11.393;15.857)

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

Data: 14, 10, 13, 16, 12, 18, 15, 11

We can calculate the sample mean and deviation with the following formulas:

$\bar X = \frac{\sum_{i=1}^n X_i}{n}$

$s = \sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}}$

$\bar X=13.625$ represent the sample mean

$\mu$ population mean (variable of interest)

s=2.669 represent the sample standard deviation

n=8 represent the sample size

Calculate the confidence interval

The confidence interval for the mean is given by the following formula:

$\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}$ (1)

In order to calculate the critical value $t_{\alpha/2}$ we need to find first the degrees of freedom, given by:

$df=n-1=8-1=7$

Since the confidence is 0.95 or 95%, the value of $\alpha=0.05$ and $\alpha/2 =0.025$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.025,7)".And we see that $t_{\alpha/2}=2.365$

Now we have everything in order to replace into formula (1):

$13.625-2.365\frac{2.669}{\sqrt{8}}=11.393$

$13.625+2.365\frac{2.669}{\sqrt{8}}=15.857$

So on this case the 95% confidence interval would be given by (11.393;15.857)

3 0

1 year ago