Question

How many 6 digit numbers greater than 2,00,000 are possible with digits ; 1,2,3,4,5,6,7,8; assuming that none of the digit gets repeated?​

Answer 1

Step-by-step explanation:

Given:-

Rate of descending the elevator = 7m/min

It start descend from 9 m above the ground level.

To Find:-

How long will it take to reach -205 m

Solution:-

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀According to the Question

It is given that elevator descends in to a mine shaft at the rate of 7m/min .If its descent starts from 9m above the ground level. we have to calculate the time taken to reach -205 m . So let's begin

As the elevator descend 9 m above from the ground level.

So , the distance descended by the elevator = -205 + (+9)

:\implies:⟹ -196m

Now it is given that the rate of descending the elevator is 7m/min. (we take the rate of descending in negative )

Let the time taken by the elevator be t min .

Therefore,

:\implies:⟹ rate = Distance/time

Substitute the value we get

:\implies:⟹ -7 = -196/t

:\implies:⟹ 7 = 196/t

:\implies:⟹ 7×t = 196

:\implies:⟹ t = 196/7

:\implies:⟹ t = 28 minutes

Hence, the time taken by the elevator is 28 minutes.

Answer 2

Step-by-step explanation:

ways to fill the remaining digits. = 720 ways. Therefore, 720, six digit even numbers can be formed