Answer:
25km/hr (take the word train as bus )
Step-by-step explanation:
Answer
Let x km/hr be the constant speed of the train,
Then Time taken to cover 300km=
x
300
hrs
Time taken to cover 300km when the speed is increased by 5km/hr=
x+5
300
hours
It is given that the time to cover 300km is reduced by 2 hours
∴
x
300
−
x+5
300
=2
⇒
x(x+5)
300(x+5)−300x
=2⇒2x
2
+10x=1500
⇒x
2
+5x−750=0⇒x
2
+30x−25x−750=0
⇒(x+30)(x−25)=0⇒x=25orx=−30
But x cannot be negative. Therefore x=25
Hence, the original speed of the train is 25km/hr
Answer:D
Step-by-step explanation:
Your answer would be 0.05 per ounce
Answer:

Step-by-step explanation:
The scientific notation:

We have:

21.8 >10
21.8 = 2.18 × 10
Thereofre:

Use


Answer:
the mean and standard deviation is 2300 and 100 respectively
Step-by-step explanation:
Given that
Mean = 2300
Standard deviation = 500
let us assume the x be the mean of living space
And, the sample is of 25 homes
We need to find out the mean and the standard deviation
So here mean = 2300
And, the standard deviation
= 500 ÷√25
= 500 ÷ 5
= 100
hence, the mean and standard deviation is 2300 and 100 respectively