Can someone help me ASAP

A boat on a river travels downstream between two points, 90 mi apart, in 1 h. The return trip against the current takes 2 1 2 h.

docker41 [41]

Answer:

A)63miles per hour.

B)27 miles per hour

Step-by-step explanation:

HERE IS THE COMPLETE QUESTION

boat on a river travels downstream between two points, 90 mi apart, in 1 h. The return trip against the current takes 2 1 2 h. What is the boat's speed (in still water)??b) How fast does the current in the river flow?

Let the speed of boat in still water = V(boat)

speed of current=V(current)

To calculate speed of boat downstream, we add speed of boat in still water and speed of current. This can be expressed as

[V(boat) +V(current)]

It was stated that it takes 1hour for the

boat to travels between two points of 90 mi apart downstream.

To calculate speed of boat against current, we will substact speed of current from speed of boat in still water. This can be expressed as

[V(boat) - V(current)]

and it was stated that it takes 2 1/2 for return trip against the Current

But we know but Speed= distance/time

Then if we input the stated values we have

V(boat) + V(current)]= 90/1 ---------eqn(1)

V(boat) - V(current) = 90/2.5----------eqn(2)

Adding the equations we have

V(boat) + V(current) + [V(boat) - V(current)]= 90/2.5 + 90/1

V(boat) + V(current) + V(boat) - V(current)]=90+36

2V(boat)= 126

V(boat)=63miles per hour.

Hence, Therefore, the speed of boat in still water is 63 miles per hour.

?b) How fast does the current in the river flow?

the speed of the current in the river, we can be calculated if we input V(boat)=63miles per hour. Into eqn(1)

V(boat) + V(current)]= 90/1

63+V(current)=90

V(current)= 27 miles per hour

Hence,Therefore, the speed of current is 27 miles per hour.

7 0

3 years ago

Need some help with multiplying algebraic fractions

Nezavi [6.7K]

Answer:

a=10, b=5, c=2, d=12

Step-by-step explanation:

Multiply each variable together

5*2=10

8*3=24

10 $x^{3}$ $y^{2}$ /24x

the coefficients (numbers) can each be divided by 2

5 $x^{3} y^{2}$ /12x

subtract the "x" exponents together

5 $x^{2} y^{2}$ /12

8 0

3 years ago

Find the sum. Write your answer in simplest form. - 4 1/6 + 5 4/7

Kitty [74]

Answer:

1 17/42.

Step-by-step explanation:

Find the common denominator, which is 42.

So change -4 1/6 to -4 7/42.

And change 5 4/7 to 5 24/52.

So add -4 7/42 + 5 24/52 and you'll get: 1 17/42.

(The decimal form of this is 1.404762)

7 0

3 years ago

Read 2 more answers

Can someone please help me with this i need it badddd

svetlana [45]

G=61°, h=9. the opposite angles are equal, and the opposite sides are equal.

7 0

3 years ago

Several years ago, the mean height of women 20 years of age or older was 63.7 inches. Suppose that a random sample of 45 women w

Karo-lina-s [1.5K]

Answer:

1. C) H0: u = 63.7 in. versus H1: u > 63.7 in.

2. B). There is a 0.18 probability of obtaining a sample mean height of exactly 64.2 inches from a population whose mean height is 63.7 inches.

3. B) Reject the null hypothesis. There is sufficient evidence to conclude that the mean height of women 20 years of age or older is greater today.

Step-by-step explanation:

1. C) H0: u = 63.7 in. versus H1: u > 63.7 in.

the null hypothesis state that over the years the mean height is 63.7in. the alternative hypothesis will be if the mean height is greater than 63.7

2. z = (variate - mean)/ (standard deviation/ $\sqrt{N}$

Z = (64.2 - 63.7)/ (20/roots 45) =0.17

meaning there is

B. There is a 0.18 probability of obtaining a sample mean height of exactly 64.2 inches from a population whose mean height is 63.7 inches.

3. if the level of significance is 0.05 or between 0.05 and 0.01, i.e. the confidence level is 95% or between 95% and 99%, the results are considered to be probably significant, i.e. the results are probably correct,

therefore, the alternative hypothesis is correct

B) Reject the null hypothesis. There is sufficient evidence to conclude that the mean height of women 20 years of age or older is greater today.

8 0

3 years ago