Step-by-step explanation:
Let the original speed of the train be x km/h.
Time taken to cover a distance of 360 km = 360/x hours.
New speed of the train = (x+5) km/h.
Time taken to cover a distance of 360 km at new speed = 360/x+5 hours.
Since, the train takes 1 hour less time,
∴360/x - 360/ x+5 = 1
⇒360 (5) = x² + 5x
⇒1800 = x² + 5x
⇒x² + 5x - 1800 = 0
⇒x² + 45x - 40x - 1800 = 0
⇒x (x+45) - 40( x +45) = 0
⇒(x+45) (x-40) = 0
⇒x = (-45), 40
But since speed cannot be in negative.
∴x = 40 km/hr.
Hence, the original speed of the train is 40 km/h.
Answer:
<2 = 75°
<3 = 75°
Step-by-step explanation:
<2 = <6
2x+15 = 45+x
or, 2x-x = 45-15
or, x = 30
so, <2 = 30×2+15 = 75
<6 = 45+30 = 75
Answered by GAUTHMATH
Answer:
x = 2
Step-by-step explanation:
Answer:
Step-by-step explanation:
Or if you mean r= m/[2(c + K)]
Answer:
The value is 
Step-by-step explanation:
From the question we are told that
The total number of students is 
The number of student that took exam in class is n = 24
The number that took make up exam is k = 1
The average score of the first 24 students is 
The standard deviation is 
The average score of the student who took make up test is 
Generally the new average is mathematically represented as
