.) Find – 4.25 +2.5.

Suppose an opaque jar contains 3 red marbles and 10 green marbles. The following exercise refers to the experiment of picking tw

kow [346]

Answer:

$\frac{5}{13}$

Step-by-step explanation:

Given,

Red marbles = 3,

Green marbles = 10,

So, the total marbles = 3 + 10 = 13,

$\because \text{Probability}=\frac{\text{Favourable outcomes}}{\text{Total outcomes}}$

Since, here replacement is not allowed,

Thus, the probability of getting a green marble and a red marble

= first red and second green + first green second red

$=\frac{3}{13}\times \frac{10}{12}+\frac{10}{13}\times \frac{3}{12}$

$=2\times \frac{3}{13}\times \frac{10}{12}$

$=\frac{30}{78}$

$=\frac{5}{13}$

Note : The probability of getting a green marble first and a red marble second

= $\frac{10}{13}\times \frac{3}{12}$

$=\frac{30}{156}$

$=\frac{5}{26}$

4 0

3 years ago

*50 points*

xxMikexx [17]

Answer:

6

Step-by-step explanation:

root the 216 as it is a cube

:edge *edge *edge =volume

Since all edges are the same, just root it

I hope this helped if it did please mark me Brainliest

6 0

3 years ago

Read 2 more answers

A college job placement office collected data about students’ GPAs and the salaries they earned in their first jobs after gradua

frez [133]

Answer:

X is the GPA

Y is the Salary

Standard deviation of X is 0.4

Standard deviation of Y is 8500

E(X)=2.9

E(Y)=47200

We are given that The correlation between the two variables was r = 0.72

a) $y = a+bx$

$b = \frac{\sum(x_i-\bar{x})(y_i-\bar{y})}{\sum(x_i-\bar{x})^2} = \frac{r \times \sqrt{var(X) \times Var(Y)}}{Var(X)} = \frac{0.72 \times \sqrt{0.4^2 \times 8500^2}}{0.4^2} = 15300$

$a=y-bx = 47200-(15300 \times 29) = 2830$

So, slope = 15300

Intercept = 2830

So, equation : $y = 2830+15300x$

b) Your brother just graduated from that college with a GPA of 3.30. He tells you that based on this model the residual for his pay is -$1880. What salary is he earning?

$y = 2830+15300 \times 3.3 = 53320$

Observed salary = Residual + predicted = -1860+53320 = 51440

c)) What proportion of the variation in salaries is explained by variation in GPA?

The proportion of the variation in salaries is explained by variation in GPA = $r^2 = (0.72)^2 =0.5184$

8 0

2 years ago

A running circuit is in the shape of a triangle with lengths of 6km, 6.5km and 7km. What are the sizes of the angles (in minutes

Rudik [331]

A triangle is an example of a class of figures referred to as plane shapes. It has three straight sides and three internal angles which sum up to $180^{o}$ . The measures of the internal angles of the triangle given in the question are A = $52.6^{o}$ , B = $59.4^{o}$ , and C = $68^{o}$ .

A triangle is an example of a class of figures referred to as plane shapes. It has three straight sides and three internal angles which sum up to $180^{o}$ .

Considering the given question, let the sides of the triangle be: a = 6 km, b = 6.5 km, and c = 7 km.

Apply the Cosine rule to have:

$c^{2}$ = $a^{2}$ + $b^{2}$ - 2ab Cos C