Answer:
4
Step-by-step explanation:
Let red marbles be x.
Blue : 2x
Red : x
Yellow : x+8
2x + x + x + 8 = 56
4x = 48
x = 12
Red marbles: 12
Blue : 24
Yellow: 20
Answer: 54 mph
Step-by-step explanation:
d-the distance
s+9 - the speed to the conference
d=6*(s+9)
s- is the speed on the way back home
d=7*s
so 6*(s+9)=7*s
6s+54=7s
-6s -6s
54= 7s-6s
s=54 mph
Answer:
10
Step-by-step explanation:
Paying off a debt over time with planned payments, so kind of like mortgage on a house.
