1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
djyliett [7]
3 years ago
5

A motorboat takes

Mathematics
1 answer:
vagabundo [1.1K]3 years ago
4 0
Recall your d = rt, distance = rate * time

let's say the boat's rate is "b" in still water, and the current's rate is "c"

as the boat goes upstream, is not really going "b" fast, the water is not still anyway, is going much slower, is going " b - c ", because the current's rate is eroding speed because is going against the current.

as the boat goes downstream, is not going "b" fast either, is going faster, is going " b + c " fast, because is going downstream and thus with the current and the current is adding speed to it.  notice, it takes longer going up, 5hrs, then coming down, 3hrs, same 150 on each way.

\bf \begin{array}{llll}
&distance&rate&time\\
&-----&-----&-----\\
upstream&150&b-r&5\\
downstream&150&b+r&3
\end{array}
\\\\\\

\begin{cases}
150=(b-r)5\\
\qquad \frac{150}{5}=b-r\\
\qquad 30=b-r\\
\qquad 30+r=\boxed{b}\\
150=(b+r)3\\
\qquad \frac{150}{3}=b+r\\
\qquad 50=b+r\\
\qquad 50=\boxed{30+r}+r
\end{cases}

solve for "r"

what's the boat's rate? well, 30+r = b
You might be interested in
This has to do with reading graphs and words per page
HACTEHA [7]

Answer:

idont konw but ask google

Step-by-step explanation:

57898765432345678909876543jgfhjfghjfhgjfgj

3 0
3 years ago
Please help i beg i never get these right
Anuta_ua [19.1K]

Answer:

\sin(105) = \frac{\sqrt 2 + \sqrt 6}{4}

Step-by-step explanation:

Given

\sin(105^o)

Required

Solve

Using sine rule, we have:

\sin(A + B) = \sin(A)\cos(B) + \sin(B)\cos(A)

This gives:

\sin(105^o) = \sin(60 + 45)

So, we have:

\sin(60 + 45) = \sin(60)\cos(45) + \sin(45)\cos(60)

In radical forms, we have:

\sin(60 + 45) = \frac{\sqrt 3}{2} * \frac{\sqrt 2}{2} + \frac{\sqrt 2}{2} * \frac{1}{2}

\sin(60 + 45) = \frac{\sqrt 6}{4} + \frac{\sqrt 2}{4}

Take LCM

\sin(60 + 45) = \frac{\sqrt 6 + \sqrt 2}{4}

Rewrite as:

\sin(60 + 45) = \frac{\sqrt 2 + \sqrt 6}{4}

Hence:

\sin(105) = \frac{\sqrt 2 + \sqrt 6}{4}

3 0
2 years ago
There are n apples in a box; this is 3/7 of all the fruits in it. How many fruits are there in the box? (n=21)
Morgarella [4.7K]

Answer:

49

Step-by-step explanation:

n is 3/7 of total fruit

n=21 apples

Here they are just telling us that the apples make up a total of 3/7 percent of the total fruit in the box. So to find the total amount of fruit from this information we just simply take the n number of apples and divide that by the percent that it represents. So basically just this;

n=21 and (n)/(3/7)=total fruit

(21)/(3/7)=21*7/3=147/3=49 total fruit and 21apples make up (3/7)% of the total fruit in the box.

Hope this helped some. Any questions please feel free to ask. Thanks!

4 0
3 years ago
What is the answer for 1/7(1,000)
12345 [234]
1/7(1000) = 1/7(7000/7)

1*7000
7*7

7000
49

1000
7

so 1/7(1000) = 1000/7 or 142 6/7
5 0
3 years ago
Read 2 more answers
Evaluate the formula V=BH/3 for B=4cm^2 and h=6 cm
Tom [10]
V=BH/3
V=(4)(6)/3
V=(24)/3
V=8
6 0
3 years ago
Read 2 more answers
Other questions:
  • What is 30/4 as a mixed fraction
    5·1 answer
  • If a bill cost $125. And they leave a $21.25 for a tip what percentage did they tip
    12·1 answer
  • Evaluate the expression,<br> -2.4+24+8
    6·2 answers
  • If the ratio of grapes to walnuts to oranges is 6:6:12, how many grapes are there if the total number of fruits is 192?
    6·1 answer
  • ANSWER !! <br> ILL GIVE 40 POINTS !!<br> DONT SKIP :(( <br> PLUS BRAINLIEST !
    12·1 answer
  • Solve for x: 5x – 2 = 13<br> GIVING BRAINLIST!! Please help
    9·2 answers
  • We are getting y=1/2x+1. Help!!!
    13·1 answer
  • Look at pic please help meh! &gt;
    8·2 answers
  • Find an expression which represents the difference when (-4x-2) is subtracted from (-8x+3) in simplest terms.
    6·2 answers
  • Determine which postulate can be used to prove the triangles are congruent then identify the valid congruency statement.
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!