Answer:
x = 387
Step-by-step explanation:
The wind acts in the opposite direction to the plane when the time is longer.
The wind acts in the same direction as the plane when the time is shorter.
Equation
d = r*t
Givens
- d = 1720
- x = plane's speed
- y = wind speed
- t1 = 5 hours
- t2 = 4 hours.
Substitution
- d = (x + y) * t
- 1720 = (x + y) * 4
- 1720 = (x - y) * 5
Since the two distances are the same, you can equate the right hand sides.
- (x + y) * 4 = (x - y)*5 Remove the brackets.
- 4x + 4y = 5x - 5y Add 5y to both sides
- 4x + 4y + 5y = 5x - 5y + 5y Combine all the terms.
- 4x + 9y = 5x Subtract 4x from both sides
- 9y + 4x - 4x = 5x - 4x Combine
- 9y = x
Now use one of the given equations with the distance
- 1720 = (x + y)*4 Substitute 9y for x
- 1720 = (9y + y) * 4 Combine
- 1720 = 10y * 4 Multiply the right
- 1720 = 40y Divide by 40
- 1720/40 = 40y/40 Do the division
- 43 = y y = wind speek
- 9y = x x = 9*y
- 9*43 = x
- x = 387 miles per hour.
You can draw a picture and you can find your answer but the answer is 1 1/3 by the way
Answer:
radius is 8cm
Step-by-step explanation: radius is half of diameter so 16/2= 8
keeping in mind that 21 months is more than a year, since there are 12 months in a year, then 21 months is really 21/12 years.
![\bf ~~~~~~ \stackrel{\textit{account A}}{\textit{Simple Interest Earned}} \\\\ I = Prt\qquad \begin{cases} I=\textit{interest earned}\dotfill &15.75\\ P=\textit{original amount deposited}\dotfill \\ r=rate\to 3\%\to \frac{3}{100}\dotfill &0.03\\ t=years\to \frac{21}{12}\dotfill &\frac{7}{4} \end{cases} \\\\\\ 15.75=P(0.03)\left( \frac{7}{4} \right)\implies \cfrac{15.75}{(0.03)\left( \frac{7}{4} \right)}=P\implies \boxed{300=P}](https://tex.z-dn.net/?f=%5Cbf%20~~~~~~%20%5Cstackrel%7B%5Ctextit%7Baccount%20A%7D%7D%7B%5Ctextit%7BSimple%20Interest%20Earned%7D%7D%20%5C%5C%5C%5C%20I%20%3D%20Prt%5Cqquad%20%5Cbegin%7Bcases%7D%20I%3D%5Ctextit%7Binterest%20earned%7D%5Cdotfill%20%2615.75%5C%5C%20P%3D%5Ctextit%7Boriginal%20amount%20deposited%7D%5Cdotfill%20%5C%5C%20r%3Drate%5Cto%203%5C%25%5Cto%20%5Cfrac%7B3%7D%7B100%7D%5Cdotfill%20%260.03%5C%5C%20t%3Dyears%5Cto%20%5Cfrac%7B21%7D%7B12%7D%5Cdotfill%20%26%5Cfrac%7B7%7D%7B4%7D%20%5Cend%7Bcases%7D%20%5C%5C%5C%5C%5C%5C%2015.75%3DP%280.03%29%5Cleft%28%20%5Cfrac%7B7%7D%7B4%7D%20%5Cright%29%5Cimplies%20%5Ccfrac%7B15.75%7D%7B%280.03%29%5Cleft%28%20%5Cfrac%7B7%7D%7B4%7D%20%5Cright%29%7D%3DP%5Cimplies%20%5Cboxed%7B300%3DP%7D)
![\bf ~~~~~~ \stackrel{\textit{account B}}{\textit{Simple Interest Earned}} \\\\ I = Prt\qquad \begin{cases} I=\textit{interest earned}\dotfill &28\\ P=\textit{original amount deposited}\dotfill \\ r=rate\to 4.9\%\to \frac{4.9}{100}\dotfill &0.049\\ t=years\to \frac{21}{12}\dotfill &\frac{7}{4} \end{cases} \\\\\\ 28=P(0.049)\left( \frac{7}{4} \right)\implies \cfrac{28}{(0.049)\left( \frac{7}{4} \right)}=P\implies \boxed{326.53\approx P}](https://tex.z-dn.net/?f=%5Cbf%20~~~~~~%20%5Cstackrel%7B%5Ctextit%7Baccount%20B%7D%7D%7B%5Ctextit%7BSimple%20Interest%20Earned%7D%7D%20%5C%5C%5C%5C%20I%20%3D%20Prt%5Cqquad%20%5Cbegin%7Bcases%7D%20I%3D%5Ctextit%7Binterest%20earned%7D%5Cdotfill%20%2628%5C%5C%20P%3D%5Ctextit%7Boriginal%20amount%20deposited%7D%5Cdotfill%20%5C%5C%20r%3Drate%5Cto%204.9%5C%25%5Cto%20%5Cfrac%7B4.9%7D%7B100%7D%5Cdotfill%20%260.049%5C%5C%20t%3Dyears%5Cto%20%5Cfrac%7B21%7D%7B12%7D%5Cdotfill%20%26%5Cfrac%7B7%7D%7B4%7D%20%5Cend%7Bcases%7D%20%5C%5C%5C%5C%5C%5C%2028%3DP%280.049%29%5Cleft%28%20%5Cfrac%7B7%7D%7B4%7D%20%5Cright%29%5Cimplies%20%5Ccfrac%7B28%7D%7B%280.049%29%5Cleft%28%20%5Cfrac%7B7%7D%7B4%7D%20%5Cright%29%7D%3DP%5Cimplies%20%5Cboxed%7B326.53%5Capprox%20P%7D)
so, clearly, you can see who's greater.