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
_____
<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.
x equals 4 and y equals 5 . so the formula would be 5x+12y=80 and if we need 4 of the small boxes we sub x for 4 and we get 5(4) =20. Next, 80 minus 20 is 60, and the equation would now be 12y=60. we now divide both sides by 12 and we get left with y=5. 5x + 12y = 80 5(4) + 12(5)=80 20+60=80. That is all. I hope that doesn't sound confusing
Answer: 54
Step-by-step explanation:
3 times the square of -3 plus -5 times -3 plus 12
3 times 9 + 15 + 12
27+15+12=
54
