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.
Answer:
6) 20
7) I think is 2.5 (im not sure)
8) 7
Step-by-step explanation:
6) (5x+9)+(3x+11)=180
8x+20=180
-20 -20
8x=160
Divide 8 on each side
x=20
7) (17x+1)=(20x-14)
17x+15 =20x
+17 +17
15 = 37x
divide 15 on each side
X=2.5
8) (3x+3)+(10-4)=90
(3x)+(10x-1)
13x-`1=90
+1 +1
13x=91
Divide 13 on each side
x=7
Step-by-step explanation:
The equations that could be used to determine the number of chicken wings and sliders in the combination meal is:
75w + 250s = 800
w = 2s
Where:
w = chicken wings
s = sliders
The two equations derived from the question are known as simultaneous equations. Both equations have to be solved together in order to determine the number of wings and sliders.
The total calories of wings = number of wings x calories of each wing
75 x w = 75w
The total calories of sliders = number of sliders x calories of each sliders
250 x s = 250s