Answer:
9/20
Step-by-step explanation:
45% can be written as
= 45/100
= 9/20
Hope it will help u..
V1 - velocity first train
v2 - velocity second train
v2 > v1
v2 - v1 = 17 mph
We know, that:
![s_1+s_2=210 \ [miles] \\ \\ t_1=t_2=2h](https://tex.z-dn.net/?f=s_1%2Bs_2%3D210%20%5C%20%5Bmiles%5D%20%5C%5C%20%5C%5C%20t_1%3Dt_2%3D2h)
So:
NOw we've got simple system of equations:
![+\begin{cases} v_2-v_1=17 \\ v_2+v_1=105\end{cases} \\ \\ 2v_2=122 \qquad /:2 \\ \\ v_2=61 \qquad [mph] \\ \\ v_2-v_1=17 \\ \\ 61-v_1=17 \\ \\ v_1=44](https://tex.z-dn.net/?f=%2B%5Cbegin%7Bcases%7D%20v_2-v_1%3D17%20%5C%5C%20v_2%2Bv_1%3D105%5Cend%7Bcases%7D%20%5C%5C%20%5C%5C%202v_2%3D122%20%5Cqquad%20%2F%3A2%20%5C%5C%20%5C%5C%20v_2%3D61%20%5Cqquad%20%5Bmph%5D%20%5C%5C%20%5C%5C%20v_2-v_1%3D17%20%5C%5C%20%5C%5C%2061-v_1%3D17%20%5C%5C%20%5C%5C%20v_1%3D44)
Velocities of these trains are 61mph and 44mph
Answer:
a) 9*π or approx 28.26
b) ∡CRB=100°
Step-by-step explanation:
As known for secants crossing each other inside the circle is coorect the following:
BR*RD=AR*RC
=> 3*RD=4*4.5
RD=6
The diameter of the circle with center P is BD=BR+RD=3+6=9
So the radius of the circle is D/2=9/2=4.5
As known the circumference of any circle can be calculated as
C=2*π*r , where r is the circle's radius
So C=2*4.5*π=9*π= approx 3.14*9=28.26
b) ∡CRB=∡ARD= (arcBC+arcAD), where arcBC and arcAD smaller arcs
BD is the circle's diameter, so arc BD=180°
So arcBC=180°-arcCOD=180°-100°=80°
Similarly arcBD=180°
arcAD=180°-arcBSA=180°-60°=120°
∡CRB= (80°+120°)/2=100°
Answer:
24
Step-by-step explanation:
Just plug each number in calculator and do multiply buy 3 and divide by 4 then add them together
