How many 5-digit numbers can be formed from the integers 1, 2, ... , 9 if no digit can appear more than twice?

1 answer:

6 0

5 digit number with no repeats
1st digit has 9 possibilities
2nd digit has 8 possibilities
3rd digit has 7 possibilities
4th digit has 6 possibilities
5th fight has 5 possibilities
Therefore the answer is:
9 x 8 x 7 x 6 x 5 = 72 x 210 = 15,120

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The vector ~v represents the displacement vector from Portland, Oregon to Houston, Texas. The vector w~ represents the displacem

Art [367]

Answer:

the displacement of the plane is $- \= w$

The displacement of plane from Portland to Akron with layover at Houston is

$\= v + \= w$

the vector which defines this displacement is $\= v + \= w =- 2500 \ km$

Step-by-step explanation:

From the question we are the

The displacement from Portland, Oregon to Houston, Texas. is $\= v$

The displacement from Houston, Texas to Akron, Ohio. is $\= w$ a

The motion of the plane in question a is in the opposite direction to vector $\= w$

So the displacement of the plane is $- \= w$

The motion of Portland to Houston to Akron is in the direction of both vector $\= v$ and $\= w$ so

The displacement of plane from Portland to Akron with layover at Houston is

$d = \= v + \= w$

From the question we are told that the plane flies over Portland to get to Anchorage, Alaska which implies that it is moving in opposite direction to the vector $\= v$

Give that distance from Portland to Houston is $\= v = 3000 km$