Answer:
37.5 hrs
Step-by-step explanation:
You do cross multiplication hours on top and weeks on the bottom.
If you meant that 1 ball can complete a full rotation in 120 mins then to have a 180 min rotation you need 1.5 balls.
Answer:
10
Step-by-step explanation:
Consider the figure attached.
Let m(R)=α degrees and m(T)=β degrees.
1.
Angle R, is an inscribed angle, intercepting the arc WTS.
This means that the measure of the arc WTS is double the measure of the angle R,
so m(arc WTS) = 2α degrees.
2.
Similarly,
Angle T, is an inscribed angle, intercepting the arc WRS. So
m(arc WRS) = 2β degrees.
3.
m(arc WTS)+m(arc WRS)=360° since these arcs cover the whole circle.
thus
2α+2β=360°
divide by 2:
α+β=180°
this means T and R are supplementary angles.
X = 13
( x + 4) / 51 = (2x - 7) / 57
585 = 45x
585/45 = 45x/45
x = 13