Answer:
25 meters per minute
150 in 6 minutes
Step-by-step explanation:
Using the magic of algebra!:
The time each train goes in 1 hour will be represented as a / b.
b is 30 more than a, so if we add 30 to a it should equal b.
a + 30 = b
In three hours, the trains are 330 miles apart.
Esentially, we're adding up the distance each train goes from the starting point to find the distance between them.
3b + 3a = 330
Now we have a system of equations to solve.
a + 30 = b
3b + 3a = 330
We want to get the variables on seperate sides of the equation for easy solving.
a + 30 = b
3b = 330 - 3a
Then get the value of the one variable the same so we can use the transitive property.
a + 30 = b
b = 110 - a
a + 30 = 110 - a
2a + 30 = 110
2a = 80
a = 40 mph
(And thus b = 70 mph)
Ans: (640-80) divided by 2=280-cost of the pair of shoes
280+80=360-cost of the dress
check: 280+360=640
The longest side of the triangle has to be less than the sum of the two other sides.
A ⇒ 7 + 8 = 15
B ⇒ 8 + 5 < 14
C ⇒ 6 + 3 < 10
D ⇒ 2 + 6 > 7
The answer is D, because the longest side length (7) is shorter than the two other side lengths (2 and 6).