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2 years ago

5

A motorboat travels 105 kilometers in 3 hours going upstream. It travels 165 kilometers going downstream in the same amount of t

ime. What is the rate of the
boat in still water and what is the rate of the current?

1 answer:

Novay_Z [31]2 years ago

8 0

Answer:

Rate in still water = 45 km/h

Rate of the current = 10 km/h.

Step-by-step explanation:

Let the rate of the current be x and rate in still water be y.

So the rate of the boat upstream is y - x and the rate downstream = x + y.

Rate upstream = distance / time

y - x = 105/3 = 35 ...... (1)

Rate downstream:

y + x = 165/3 = 55 .......(2)

Adding (1) + (2):

2y = 90

y = 45 km/h.

Using equation (1):

45 - x = 35

x = 45-35 = 10 km/h.

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Solve If QR = 6x + 1, PR = 14x - 13, and PQ = 5x - 2, find PR

solong [7]

Answer:

P____Q____R

PR= PQ+ QR

(14x-13) = (5x-2)+(6x+1)

14x-13= 11x – 1

14x – 11x = 13–1

3x = 12

x= 12/ 3

x= 4

PR= 14x – 13 = 14 (4) – 13 = 18 – 13= 5

If you want (PQ , QR ) this is the solution

PQ =5x-2=5(4)-2=20-2=18

QR =6x+1=6(4)+1=24+1=25

I hope I helped you^_^

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2 years ago

The 5th term in a geometric sequence is 160. The 7th term is 40. What are possible values of the 6th term of the sequence?

omeli [17]

Answer:

C. The 6th term is positive/negative 80

Step-by-step explanation:

Given

Geometric Progression

$T_5 = 160$

$T_7 = 40$

Required

$T_6$

To get the 6th term of the progression, first we need to solve for the first term and the common ratio of the progression;

To solve the common ratio;

Divide the 7th term by the 5th term; This gives

$\frac{T_7}{T_5} = \frac{40}{160}$

Divide the numerator and the denominator of the fraction by 40

$\frac{T_7}{T_5} = \frac{1}{4}$ ----- equation 1

Recall that the formula of a GP is

$T_n = a r^{n-1}$

Where n is the nth term

So,

$T_7 = a r^{6}$

$T_5 = a r^{4}$

Substitute the above expression in equation 1

$\frac{T_7}{T_5} = \frac{1}{4}$ becomes

$\frac{ar^6}{ar^4} = \frac{1}{4}$

$r^2 = \frac{1}{4}$

Square root both sides

$r = \sqrt{\frac{1}{4}}$

r = ± $\frac{1}{2}$

Next, is to solve for the first term;

Using $T_5 = a r^{4}$

By substituting 160 for T5 and ± $\frac{1}{2}$ for r;

We get

$160 = a \frac{1}{2}^{4}$

$160 = a \frac{1}{16}$

Multiply through by 16

$16 * 160 = a \frac{1}{16} * 16$

$16 * 160 = a$

$2560 = a$

Now, we can easily solve for the 6th term

Recall that the formula of a GP is

$T_n = a r^{n-1}$

Here, n = 6;

$T_6 = a r^{6-1}$

$T_6 = a r^5$

$T_6 = 2560 r^5$

r = ± $\frac{1}{2}$

So,

$T_6 = 2560( \frac{1}{2}^5)$ or $T_6 = 2560( \frac{-1}{2}^5)$

$T_6 = 2560( \frac{1}{32})$ or $T_6 = 2560( \frac{-1}{32})$

$T_6 = 80$ or $T_6 = -80$

$T_6 =$ ±80

Hence, the 6th term is positive/negative 80

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2 years ago

Find the measure of the ndicaited angle to the nearest degree 35 and 38

12345 [234]

The measure of the indicated angle to the nearest degrees is 23 degrees.

<h3>How to find angle of a right angle triangle?</h3>

The angle of a right angle triangle can be found as follows:

Therefore, the angle can be found using trigonometric ratios as follows;

cos ∅ = adjacent / hypotenuse

Therefore,

adjacent side = 35 units

hypotenuse side = 38 units

Hence,

cos ∅ = 35 / 38

∅ = cos⁻¹ 0.92105263157

∅ = 22.9272842944

∅ ≈ 23 degrees.

learn more on triangle here: brainly.com/question/20759265

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1 year ago

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AWNSER: $90.75

Shelly earns $90.75 in compound interest after 3 years. All together she has $695.75.

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3 years ago

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GenaCL600 [577]

Given:
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3 years ago

Read 2 more answers