What value of t makes P(t) = 21?<br> A. 1<br> B. 2<br> C. 3<br> D. 4

ludmilkaskok [199]

Add all the numbers of the triangle and then divide them by the sides

7 0

3 years ago

A STUDENT FINISHES THEIR FISR HALF OF AN EXAM IN 2/3 THE TIME IT TAKES HIM TO FINISH THE SECOND HALF. IF THE ENTIRE EXAM TAKES H

shepuryov [24]

Answer: First half was 24 minutes

Step-by-step explanation:

Let the time taken to finish the second half be y.

Since the student used 2/3 of the second half time to finish the first half, first half = 2/3 × y = 2y/3

The entire exam is an hour which equals 60 minutes

First half + Second half = 60minutes

Note that first half is denoted as 2y/3 and second half is denoted by y.

2y/3 + y = 60

5y/3 = 60

Cross multiply

5y = 60 × 3

5y = 180

y = 180/5

y = 36

Second half took 36 minutes

Since first half is 2y/3, it will be:

(2×36) / 3

= 72/3

= 24minutes

First half took 24 minutes.

8 0

3 years ago

With a line 7 cm long. Use a set square and a ruler and draw perpendicular lines at both ends

Setler79 [48]

Answer:

See Explanation

Step-by-step explanation:

According to the Question,

Steps of construction:

Step I - Draw a line segment AB = 7 cm with the help ruler.

Step II - with vertex A, by using compass take more than half of AB and draw arcs, one on each side of AB.

Step III - with vertex B, by using a compass with the same length, cut the previous arcs at X and Y respectively.

Step IV - with help of the ruler join the points X and Y Thus XY is the perpendicular bisector of line AB.

(For Diagram please find in attachment)

5 0

3 years ago

1. Shay found that she hit the bull's-eye when throwing darts 2/10 times. If she

viva [34]

<h2>Answer:</h2><h2>If she continues to throw darts 75 more times, she could predict to hit the </h2><h2>bull's-eye 15 times.</h2>

Step-by-step explanation:

Shay found that she hit the bull's-eye when throwing darts $\frac{2}{10}$ times = $\frac{1}{5}$ .

In five times, she will hit the dart once.

If she continues to throw darts 75 more times,

the probability that she will hit the bull's eye = $\frac{1}{5}$ (75) = 15 times.

If she continues to throw darts 75 more times, she could predict to hit the

bull's-eye 15 times.

6 0

3 years ago

The Slow Ball Challenge or The Fast Ball Challenge.

cupoosta [38]

Answer:

Fast ball challenge

Step-by-step explanation:

Given

Slow Ball Challenge

$Pitches = 7$

$P(Hit) = 80\%$

$Win = \$60$

$Lost = \$10$

Fast Ball Challenge

$Pitches = 3$

$P(Hit) = 70\%$

$Win = \$60$

$Lost = \$10$

Required

Which should he choose?

To do this, we simply calculate the expected earnings of both.

Considering the slow ball challenge

First, we calculate the binomial probability that he hits all 7 pitches

$P(x) =^nC_x * p^x * (1 - p)^{n - x}$

Where

$n = 7$ --- pitches

$x = 7$ --- all hits

$p = 80\% = 0.80$ --- probability of hit

So, we have:

$P(x) =^nC_x * p^x * (1 - p)^{n - x}$

$P(7) =^7C_7 * 0.80^7 * (1 - 0.80)^{7 - 7}$

$P(7) =1 * 0.80^7 * (1 - 0.80)^0$

$P(7) =1 * 0.80^7 * 0.20^0$

Using a calculator:

$P(7) =0.2097152$ --- This is the probability that he wins

i.e.

$P(Win) =0.2097152$

The probability that he lose is:

$P(Lose) = 1 - P(Win)$ ---- Complement rule

$P(Lose) = 1 -0.2097152$

$P(Lose) = 0.7902848$

The expected value is then calculated as:

$Expected = P(Win) * Win + P(Lose) * Lose$

$Expected = 0.2097152 * \$60 + 0.7902848 * \$10$

Using a calculator, we have:

$Expected = \$20.48576$

Considering the fast ball challenge

First, we calculate the binomial probability that he hits all 3 pitches

$P(x) =^nC_x * p^x * (1 - p)^{n - x}$

Where

$n = 3$ --- pitches

$x = 3$ --- all hits

$p = 70\% = 0.70$ --- probability of hit

So, we have:

$P(3) =^3C_3 * 0.70^3 * (1 - 0.70)^{3 - 3}$

$P(3) =1 * 0.70^3 * (1 - 0.70)^0$

$P(3) =1 * 0.70^3 * 0.30^0$

Using a calculator:

$P(3) =0.343$ --- This is the probability that he wins

i.e.

$P(Win) =0.343$

The probability that he lose is:

$P(Lose) = 1 - P(Win)$ ---- Complement rule

$P(Lose) = 1 - 0.343$

$P(Lose) = 0.657$

The expected value is then calculated as:

$Expected = P(Win) * Win + P(Lose) * Lose$

$Expected = 0.343 * \$60 + 0.657 * \$10$

Using a calculator, we have:

$Expected = \$27.15$

So, we have:

$Expected = \$20.48576$ -- Slow ball

$Expected = \$27.15$ --- Fast ball

<em>The expected earnings of the fast ball challenge is greater than that of the slow ball. Hence, he should choose the fast ball challenge.</em>

5 0

3 years ago

What value of t makes P(t) = 21? A. 1 B. 2 C. 3 D. 4