All categories

3 years ago

When I add a number to another number four times as big, the result is 30. find the first number

Mathematics

2 answers:

Leno4ka [110]3 years ago

4 0

Let's assume the number is N

According to the question, 

when I add a number to another number four times as big, the result is 30.

$x+4x=30\\\\5x=30\\\\x=\dfrac{30}{5}\\\\x=\frak{6}$

Alex73 [517]3 years ago

3 0

Answer:

x = 6

Step-by-step explanation:

Let x = first number

x+4x = 30

5x = 30

Divide by 5

5x/5 =30/5

x = 6

You might be interested in

If there are 1,800 members in the gym, how many are men?

Eva8 [605]

Answer:

1050

Step-by-step explanation:

8 0

3 years ago

What is the ratio for the volumes of two similar cylinders, given that the ratio of their heights and radii is 2:3?

ankoles [38]

Answer:

C IS YOUR ANSER.

Step-by-step explanation:

4 0

3 years ago

In a random sample of students who took the SAT test, 427 had paid for coaching courses and the remaining 2733 had not. Calculat

Dvinal [7]

Answer:

The 95% confidence interval for the proportion of students who get coaching on the SAT is (0.1232, 0.147).

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the z-score that has a p-value of $1 - \frac{\alpha}{2}$ .

427 had paid for coaching courses and the remaining 2733 had not.

This means that $n = 427 + 2733 = 3160, \pi = \frac{427}{3160} = 0.1351$

95% confidence level

So $\alpha = 0.05$ , z is the value of Z that has a p-value of $1 - \frac{0.05}{2} = 0.975$ , so $Z = 1.96$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.1351 - 1.96\sqrt{\frac{0.1351*0.8649}{3160}} = 0.1232$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.1351 + 1.96\sqrt{\frac{0.1351*0.8649}{3160}} = 0.147$

The 95% confidence interval for the proportion of students who get coaching on the SAT is (0.1232, 0.147).

8 0

3 years ago

Which of the following is most likely the next step in the series

natima [27]

Answer:

Step-by-step explanation:

In the pattern, there are some similarities with the first three circles.

1. The number is on the blue half.

2. The halves switch spots, red-blue, blue-red, red-blue.

So, the next one should have the number on the blue half and the next pattern should be red-blue, blue-red, red-blue, and blue-red.

Which one has both the number on the blue half and the pattern blue-red?

Hoped this helped.

5 0

3 years ago

What is the solution for the equation StartFraction 5 Over 3 b cubed minus 2 b squared minus 5 EndFraction = StartFraction 2 Ove

wolverine [178]

Answer:

The solutions are:

$b=0,\:b=4$

Step-by-step explanation:

Considering the expression

$\frac{5}{3b^3-2b^2-5}=\frac{2}{b^3-2}$

Solving the expression

$\frac{5}{3b^3-2b^2-5}=\frac{2}{b^3-2}$

$\mathrm{Apply\:fraction\:cross\:multiply:\:if\:}\frac{a}{b}=\frac{c}{d}\mathrm{\:then\:}a\cdot \:d=b\cdot \:c$

$5\left(b^3-2\right)=\left(3b^3-2b^2-5\right)\cdot \:2$

$5b^3-10=6b^3-4b^2-10$

$\mathrm{Switch\:sides}$

$6b^3-4b^2-10=5b^3-10$

$6b^3-4b^2-10+10=5b^3-10+10$

$6b^3-4b^2=5b^3$

$\mathrm{Subtract\:}5b^3\mathrm{\:from\:both\:sides}$

$6b^3-4b^2-5b^3=5b^3-5b^3$

$b^3-4b^2=0$

$Using\:the\:Zero\:Factor\:Principle:$ $if\:\mathrm ab=0\:\mathrm{then}\:a=0\:\mathrm{or}\:b=0\:\left(\mathrm{or\:both}\:a=0\:\mathrm{and}\:b=0\right)$

So,

$b=0,b-4=0$

$b=0,b=4$

Therefore, the solutions are:

$b=0,\:b=4$

4 0

3 years ago

Read 2 more answers