Answer:
Let the speed of the train be x km/h.
Case 1:
Distance = 288 km
Speed = x km/h
Time = Distance/Speed
= 288/x h
Case 2:
Distance = 288 km
Speed = (x+4) km/h
Time = 288/x + 4 h
Since 288/x > 288/x + 4
288/x - 288/x+4 = 1
288[1/x - 1/x+4 ] = 1
[ x + 4 - x / x(x + 4) ] = 1/288
[4 / x^2 + 4x ] = 1/288
x^2 + 4x = 1152
x^2 + 4x - 1152 = 0
x^2 + 36x - 32x - 1152 = 0
x(x + 36) - 32(x + 36) = 0
(x + 36)(x - 32) = 0
x + 36 = 0 , x - 32 = 0
x = -36 , x = 32
x = -36 , rejected since speed cannot be negative.
Therefore , speed of the train = 32 km/h
Answer:
A not similar
Step-by-step explanation:
72 × 2 = 144
78 × 2 = 156
2.75%= convert it to a decimal
.0275
Now, multiply that by 20.
20*.0275= 0.55
0.55 is 2.75% of 20.
I hope this helps!
~kaikers
Answer:
-4/3 radians
Step-by-step explanation:
let x = -240 degree
180 degree = π radians,
we want to convert x degrees to radians
x × π /180 radians
-240× π /180 radians
-4/3 radians
