Mathematics, 14.11.2019 18:31 ttaysia

You decide to enter in a rowing competition. to train, you go to the boat house and begin rolling down stream. you row for the same amount of time upstream and downstream, travel down stream for 2400 m, but only one sixth that distance upstream. the current travels at a rate of 10 m/s. what is the time you spend rowing down stream? how fast would you be rolling in stillwater?

Answers: 3

Show answers

Answers

Answer from: brooklyn674

Time spent rowing down stream $=100\ seconds$

Speed of boat in still water $=14\ ms^{-1}$

Step-by-step explanation:

Let speed of boat in still water be $= x\ ms^{-1}$

Speed of current $= 10\ ms^{-1}$

Speed of boat down stream = $\textrm{Speed of boat in still water +Speed of current}= (x+10)\ ms^{-1}$

Distance rowed down stream = 2400 m

Time spent rowing down stream = $\frac{Distance}{Speed}=\frac{2400}{x+10}\ s$ = $\frac{Distance}{Speed}=\frac{2400}{x+10}\ s$

Speed of boat up stream = $\textrm{Speed of boat in still water -Speed of current}= (x-10)\ ms^{-1}$

Distance rowed up stream = $\frac{1}{6} \textrm{ of distance rowed downstream}=\frac{1}{6}\times 2400 = 400\ m$

Time spent rowing up stream = $\frac{Distance}{Speed}=\frac{400}{x-10}\ s$

We know that,

$\textrm{Time spent rowing down stream =Time spent rowing up stream}$

So,

$\frac{2400}{x+10}=\frac{400}{x-10}$

Cross multiplying

2400(x-10)=400(x+10)

Dividing both sides by 400

$\frac{2400(x-10)}{400}=\frac{400(x+10)}{400}$

6(x-10)=x+10

6x-60=x+10

Adding 60 to both sides.

6x-60+60=x+10+60

6x=x+70

Subtracting both sides by

6x-x=x+70-x

5x=70

Dividing both sides by 5.

$\frac{5x}{5}=\frac{70}{5}$

∴ x=14

Speed of boat in still water $=14\ ms^-1$

Time spent rowing down stream = $\frac{2400}{14+10}=\frac{2400}{24}=100\ s$

Answer from: Quest

something that characterises a right triangle is the fact that we may use pythagoras' theorem to find any one of its sides given that we have the length of the other two sides. here, we have the length of the hypotenuse, √(87) yd, and one other side, √(23) yd, thus we can easily find the length of the remaining side using pythagoras' theorem as defined below:

c^2 = a^2 + b^2, where c is the length of the hypotenuse, and a and b are the lengths of the other two sides.

thus, given that c = √(87) and a = √(23), we may substitute these into the formula we defined above to get:

c^2 = a^2 + b^2

(√87)^2 = (√23)^2 + b^2 (substitute c = √87 and a = √23 into the equation)

87 = 23 + b^2 (evaluate (√87)^2 = 87 and (√23)^2 = 23 - remember that the square root of a number, squared will equal that very same number)

64 = b^2 (subtract 23 from both sides)

√64 = b (take the square root of both sides)

8 = b (evaluate √64 = 8)

therefor, the length of the unknown leg in the right triangle is 8 yd (first answer).

What is the length of the unknown leg in the right triangle ?

Answer from: Quest

answer: the 4 kilogram bag

step-by-step explanation: this is because if you divide the number of kilograms into the total it will tell you how much each individual kilogram would be worth. 2 kilos is 7 and change 3 would be around 6 ish and the 4 kilo would be 4.6 and change and the 5 kilos would be like 4.88

Another question on Mathematics

Mathematics, 21.06.2019 14:00

Easy points boii. read it. ya. fresh

Answers: 1

Answer

Mathematics, 22.06.2019 01:50

For the right triangle shown, the lengths of two sides are given. find the third side. leave your answer in simplified, radical form.

Answers: 1

Answer

Mathematics, 22.06.2019 02:00

Angles 1 and 2 are complimentary angles. angle 1 = 52 degrees. what is the measure of angle 2?

Answers: 1

Answer

Mathematics, 22.06.2019 04:30

Jocelyn estimates that a piece of wood measures 5.5 cm. if it actually measures 5.62 cm, what is the percent error of jocelyn’s estimate? a. 2.13% b. 2.18% c. 12% d. 46.83%

Answers: 2

Answer

You know the right answer?

You decide to enter in a rowing competition. to train, you go to the boat house and begin rolling do...

Questions