9514 1404 393
Answer:
7.83 km/h
Step-by-step explanation:
At her constant pace, Nina's time for 6 km will be found by the proportion ...
(time for 6 km)/(6 km) = (time for 9 km)/(9 km)
time for 6 km = (6 km)/(9 km) × (75 min) = 50 min
Jo's time for the same distance will be 4 minutes less: 50 -4 = 46 min. Jo's speed is ...
speed = distance/time
= (6 km)/(46/60 h) = 360/46 h ≈ 7.83 km/h . . . . Jo's speed
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<em>Additional comment</em>
From the 6 km point, the remaining race is half the distance already run, so will take half the time already taken. As we know, Nina will finish in 25 more minutes; Jo will finish in 46/2 = 23 more minutes, 2 minutes ahead of Nina.
Let O be the center of a circle. If <span>the measure of arc RS is 84 degrees, then m∠SOR=84^{0}. The triangle SOR is isoscales (because SO=OR as radii), so m∠RSO=m∠ORS=(180^{0}-84^{0}):2=48^{0}.
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Line RU is tangent to the circle in point R, this means that m∠ORU=90^{0}.
Consider the triangle SRU. m∠RSU=30^{0} and m∠SRU=48^{0}+90^{0}=138^{0}, then m∠RUS=180^{0}-30^{0}-138^{0}=12^{0}.
ANSWER: Correct choice B - 12^{0}.
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Answer:
x = 2
or 14.8
Step-by-step explanation:
First find the missing leg of the right triangle.
8²-3²=x²
x =
then double is to get x in the drawing
x = 2 or 14.8
Answer: 
or 
Step-by-step explanation:
To solve this problem you must:
- Convert the mixed numbers to fractions, as following:
- Multiply both fractions. Mutilply the numerators and the denominators:
- Simplify. Therefore, you obtain that the answer is:
or
