Mathematics, 17.10.2019 00:30 zandariouslee
Petes boat can travel 48 miles upstream in 4 hours. the return trip takes 3 hours. find the speed of the boat in still water and the speed of the current.
Answers: 3
![\bf \begin{cases} b=\textit{rate of the boat}\\ r=\textit{rate of the river} \end{cases}\qquad thus \\\\\\ \begin{array}{lccclll} &distance&rate&time(hrs)\\ &----&----&----\\ upstream&48&b-r&4\\ downstream&48&b+4&3 \end{array} \\\\\\ \begin{cases} 48=(b-r)(4)\to 48=4b-4r\\\\ \frac{48-4b}{-4}=r\\ --------------\\ 48=(b+r)(3)\\ -----------------------------\\\\ thus\\\\ 48=\left[ b+\left(\boxed{\frac{48-4b}{-4}}\right) \right] (3) \end{cases}](/tpl/images/0326/7160/88aa0.png)
Another question on Mathematics
Mathematics, 21.06.2019 18:00
The swimming pool is open when the high temperature is higher than 20∘c. lainey tried to swim on monday and thursday (which was 3 days later). the pool was open on monday, but it was closed on thursday. the high temperature was 30∘c on monday, but decreased at a constant rate in the next 3 days. write an inequality to determine the rate of temperature decrease in degrees celsius per day, d, from monday to thursday.
Answers: 1
Mathematics, 21.06.2019 19:10
What is the quotient? x+5/ 3x²+4x+5 © 3x2 – 11 + x + s 3x – 11 + 60 x + 5 o 3x2 - 11 - 50 x + 5 3x – 11 - - x + 5
Answers: 3
Mathematics, 21.06.2019 19:30
How long must $542 be invested at a rate of 7% to earn $303.52 in interest? in a easier way
Answers: 1
You know the right answer?
Petes boat can travel 48 miles upstream in 4 hours. the return trip takes 3 hours. find the speed of...
Questions
Physics, 09.07.2019 10:40
Spanish, 09.07.2019 10:40
Arts, 09.07.2019 10:40
Mathematics, 09.07.2019 10:40
History, 09.07.2019 10:40
Mathematics, 09.07.2019 10:40
